Initial commit

2025-04-13 20:30:02 +02:00
commit 4f8e93c2c6
37 changed files with 2945 additions and 0 deletions
--- a/.gitignore
+++ b/.gitignore
@@ -0,0 +1,25 @@
+/target/
+!.mvn/wrapper/maven-wrapper.jar
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+
+### NetBeans ###
+/nbproject/private/
+/build/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
--- a/pom.xml
+++ b/pom.xml
@@ -0,0 +1,62 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <groupId>org.tenvoorde</groupId>
+    <artifactId>geocaching</artifactId>
+    <version>1.0-SNAPSHOT</version>
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <configuration>
+                    <source>11</source>
+                    <target>11</target>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
+    <dependencies>
+        <dependency>
+            <groupId>org.apache.commons</groupId>
+            <artifactId>commons-lang3</artifactId>
+            <version>3.9</version>
+        </dependency>
+        <dependency>
+            <groupId>de.grundid.opendatalab</groupId>
+            <artifactId>geojson-jackson</artifactId>
+            <version>1.12</version>
+        </dependency>
+        <dependency>
+            <groupId>org.locationtech.jts</groupId>
+            <artifactId>jts-core</artifactId>
+            <version>1.16.1</version>
+        </dependency>
+        <dependency>
+            <groupId>org.wololo</groupId>
+            <artifactId>jts2geojson</artifactId>
+            <version>0.14.3</version>
+        </dependency>
+        <dependency>
+            <groupId>org.projectlombok</groupId>
+            <artifactId>lombok</artifactId>
+            <version>1.18.12</version>
+        </dependency>
+        <dependency>
+            <groupId>com.google.guava</groupId>
+            <artifactId>guava</artifactId>
+            <version>28.2-jre</version>
+        </dependency>
+        <dependency>
+            <groupId>org.apache.commons</groupId>
+            <artifactId>commons-math3</artifactId>
+            <version>3.6.1</version>
+        </dependency>
+        <dependency>
+            <groupId>commons-codec</groupId>
+            <artifactId>commons-codec</artifactId>
+            <version>1.14</version>
+        </dependency>
+    </dependencies>
+</project>
--- a/src/main/java/Determinant.java
+++ b/src/main/java/Determinant.java
@@ -0,0 +1,38 @@
+
+public class Determinant {
+
+	static int d1 = det1(7,2,4,2,8,7);
+	static int d2 = det2(7,2,4,2,8,7);
+	
+	public static void main(String[] args) {
+		for (int n1 = 0; n1 <= 9; n1++) {
+			for (int n2 = 0; n2 <= 9; n2++) {
+				for (int n3 = 0; n3 <= 9; n3++) {
+					for (int e1 = 0; e1 <= 9; e1++) {
+						for (int e2 = 0; e2 <= 9; e2++) {
+							for (int e3 = 0; e3 <= 9; e3++) {
+//								int det1 = -15 * e1 - 5 * e2 + 40 * e3 + 2 * e2 * n1 - 7 * e3 * n1 - 2 * e1 * n2
+//										+ 3 * e3 * n2 + 7 * e1 * n3 - 3 * e2 * n3;
+//								int det2 = 4 + 20 * e1 + 21 * e1 * e2 - 7 * e3 - 6 * e2 * n1 - 10 * e3 * n1 - 10 * n2
+//										- 7 * e2 * n2 + 5 * e2 * n1 * n2 - 6 * e1 * n3 + 3 * e3 * n1 * n3 + 2 * n2 * n3;
+								if (det1(n1,n2,n3,e1,e2,e3) == d1 && det2(n1,n2,n3,e1,e2,e3) == d2) {
+									System.out.println("" + n1 + n2 + n3 + e1 + e2 + e3);
+								}
+							}
+						}
+					}
+				}
+			}
+		}
+	}
+	
+	static int det1(int n1, int n2, int n3, int e1, int e2, int e3) {
+		return -15 * e1 - 5 * e2 + 40 * e3 + 2 * e2 * n1 - 7 * e3 * n1 - 2 * e1 * n2
+				+ 3 * e3 * n2 + 7 * e1 * n3 - 3 * e2 * n3;
+	}
+	
+	static int det2(int n1, int n2, int n3, int e1, int e2, int e3) {
+		return 4 + 20 * e1 + 21 * e1 * e2 - 7 * e3 - 6 * e2 * n1 - 10 * e3 * n1 - 10 * n2
+				- 7 * e2 * n2 + 5 * e2 * n1 * n2 - 6 * e1 * n3 + 3 * e3 * n1 * n3 + 2 * n2 * n3;
+	}
+}
--- a/src/main/java/Grutten.java
+++ b/src/main/java/Grutten.java
@@ -0,0 +1,16 @@
+
+public class Grutten {
+
+
+	private static long josephus(long total, int skip) {
+		long g = 1;
+		for (long i = 1; i <= total; i++) {
+			g = ((g + skip - 1) % i) + 1;
+		}
+		return g;
+	}
+	public static void main(String[] args) {
+		System.out.println(josephus(7382786182L, 18));
+		
+	}
+}
--- a/src/main/java/LadderProblem.java
+++ b/src/main/java/LadderProblem.java
@@ -0,0 +1,31 @@
+
+//* @author: 82638882@163.com
+import java.io.*;
+import java.util.Arrays;
+
+public class LadderProblem {
+	public static void main(String[] args) throws IOException {
+		// String[] ss = in.readLine().split(" ");
+		// double x = Double.parseDouble(ss[0]);
+		// double y = Double.parseDouble(ss[1]);
+		// double c = Double.parseDouble(ss[2]);
+		double x = 10;
+		double y = 12;
+		double c = 5;
+
+		double max = Math.min(x, y), min = 0;
+		for (int i = 0; max - min > 0.0000000001; i++) {
+			double mid = (min + max) / 2;
+			double d1 = Math.sqrt(x * x - mid * mid);
+			double d2 = Math.sqrt(y * y - mid * mid);
+			if (c * (d1 + d2) == (d1 * d2)) {
+				min = max = mid;
+				break;
+			} else if (c * (d1 + d2) > (d1 * d2))
+				max = mid;
+			else
+				min = mid;
+		}
+		System.out.printf("%.10f\n", (min + max) / 2);
+	}
+}
--- a/src/main/java/Slak.java
+++ b/src/main/java/Slak.java
@@ -0,0 +1,26 @@
+import java.math.BigDecimal;
+import java.math.MathContext;
+
+public class Slak {
+	
+	private static final double INIT_LENGTE = 1;
+	private static final double GROEI_PER_DAG = 1;
+	private static final double WANDELING_PER_DAG = 0.12;
+	
+	public static void main(String[] args) {
+		double lengte_touw = INIT_LENGTE;
+		//noinspection deprecation
+		BigDecimal positie = new BigDecimal(0).setScale(10, BigDecimal.ROUND_HALF_UP);
+//		double positie = 0;
+		long dag = 0;
+		
+		do {
+			dag++;
+			positie = positie.add(new BigDecimal(WANDELING_PER_DAG));
+			if (positie.compareTo(new BigDecimal(lengte_touw)) > 0) break;
+			lengte_touw += GROEI_PER_DAG;
+			positie = positie.multiply(new BigDecimal(lengte_touw / (lengte_touw - GROEI_PER_DAG)));
+		} while (positie.compareTo(new BigDecimal(lengte_touw)) < 0);
+		System.out.println(dag);
+	}
+}
--- a/src/main/java/SlakJohan.java
+++ b/src/main/java/SlakJohan.java
@@ -0,0 +1,24 @@
+
+public class SlakJohan {
+
+	public static void main(String[] args) {
+		double slak = 0;
+		for (int i = 1; i < 200000000; i++) {
+			slak = (slak + 0.05); // actie 1: schuiven
+			if (slak >= i) { // actie 2: checken
+				System.out.println("Lengte touw = " + (i + 1) + ", slak = " + slak);
+				break;
+			}
+			slak *= ((i + 1) / (double) i); // 3: direct daarna uitrekken
+			if (i < 10) { // debug
+				System.out.println(
+						"Slak[" + i + "] = " + slak + ", lengte touw = " + (i + 1) + ", dif = " + (slak - ((i + 1))));
+			}
+			if (i % 100000 == 0) { // debug
+				System.out.println(
+						"Slak[" + i + "] = " + slak + ", lengte touw = " + (i + 1) + ", dif = " + (slak - ((i + 1))));
+			}
+		}
+		System.out.println("Lengte touw geen uitkomst");
+	}
+}
--- a/src/main/java/Test.java
+++ b/src/main/java/Test.java
@@ -0,0 +1,131 @@
+import java.io.BufferedWriter;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.OutputStreamWriter;
+import java.io.Writer;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.ArrayList;
+import java.util.Random;
+
+public class Test {
+
+	// published: 200479, 468608
+	// cache: 198667, 467811
+	private static final int foost = 108549;
+	private static final int fnoord = 480361;
+	//108549, 
+	private static final int min_distance = 3219;
+	private static final int max_distance = 10000;
+	
+	private static final String filename = "d:\\temp\\gc6dyy3.txt";
+	
+	@SuppressWarnings("unused")
+	public static void main(String[] args) throws IOException {
+
+		// snail();
+		test();
+		if (0 < 1) return;
+
+		Random generator = new Random();
+		Long oost;
+		Long noord;
+		Long distance;
+
+		int step = 0;
+
+		try (BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(filename), "utf-8"))) {
+
+			do {
+				oost = (long) generator.nextInt(900000) + 100000;
+				noord = (long) generator.nextInt(900000) + 100000;
+				distance = (long) Math.sqrt((oost - foost) * (oost - foost) + (noord - fnoord) * (noord - fnoord));
+
+				if (distance > min_distance && distance < max_distance) {
+					writer.write(oost.toString());
+					writer.write(noord.toString());
+
+					step++;
+
+					if (step % 12 == 0) {
+						writer.newLine();
+					}
+				}
+			} while (step < 12000);
+		} catch (IOException e) {
+			e.printStackTrace();
+		}
+	}
+
+	private static void test() throws IOException {
+		Path path = Paths.get(filename);
+		byte[] data = Files.readAllBytes(path);
+		int goed = 0;
+		
+		for (int pos = 0; pos < data.length - 13; pos++) {
+			String oost = "";
+			String noord = "";
+			int subpos = pos;
+
+			for (int i = 1; i <= 6; i++) {
+				while (data[subpos] == 13 || data[subpos] == 10) {
+					subpos++;
+				}
+
+				oost += Integer.toString(data[subpos] - '0');
+				subpos++;
+			}
+
+			for (int i = 1; i <= 6; i++) {
+				while (data[subpos] == 13 || data[subpos] == 10) {
+					subpos++;
+				}
+
+				noord += Integer.toString(data[subpos] - '0');
+				subpos++;
+			}
+
+			Long lnoord = Long.parseLong(noord);
+			Long loost = Long.parseLong(oost);
+			Long distance = (long) Math.sqrt((loost - foost) * (loost - foost) + (lnoord - fnoord) * (lnoord - fnoord));
+
+			if (distance < min_distance) {
+				System.out.println(oost + " " + noord + " " + distance);
+			} else {
+				goed++;
+			}
+		}
+		System.out.println(goed);
+	}
+
+	private static void snail() {
+
+		double length = 20;
+		double walk = 1;
+		double position = 0;
+		double growth = 20;
+		long step = 0;
+
+		do {
+			step++;
+			position += walk;
+			length += growth;
+			position *= (length / (length - growth));
+		} while (position < length);
+
+		System.out.println(step);
+	}
+
+	private static void test2() {
+		var a = new ArrayList<>();
+		a.size();
+		int[] b;
+		b = new int[5];
+		int c = b.length;
+		String d = "abc";
+		d.length();
+
+
+	}
+}
--- a/src/main/java/TrackableCrawler.java
+++ b/src/main/java/TrackableCrawler.java
@@ -0,0 +1,4 @@
+
+public class TrackableCrawler {
+
+}
--- a/src/main/java/Traveling.java
+++ b/src/main/java/Traveling.java
@@ -0,0 +1,155 @@
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import org.apache.commons.lang3.tuple.Pair;
+
+public class Traveling {
+
+	private static double minimum = 100000;
+	private static Map<Pair<City,City>, Double> distances = new HashMap<>();
+	
+	class tspThread implements Runnable {
+		List<City> toVisit, visited;
+		
+		public tspThread(List<City> toVisit, List<City> visited) {
+			this.toVisit = toVisit;
+			this.visited = visited;
+		}
+		
+		public void run() {
+			System.out.println("Thread gestart met begin " + this.visited.get(0));
+			findBestRoute(toVisit, visited);
+			System.out.println("--- thread klaar ---");
+
+		}
+	}
+	
+	public void start() {
+		List<City> cities = new ArrayList<>(Arrays.asList(
+				new City("n", 6, 1)
+				, new City("f", 3, 2)
+				, new City("a", 5, 4)
+				, new City("b", 7, 4)
+				, new City("k", 10, 4)
+				, new City("g", 1, 5)
+				, new City("c", 9, 6)
+				, new City("e", 4, 7)
+				, new City("d", 8, 8)
+				, new City("q", 10, 8)
+				, new City("h", 4, 10)
+				, new City("p", 7, 10)
+				, new City("m", 10, 10)
+
+
+
+
+
+			));
+		
+		buildDistancesMap(cities);
+
+		for (City cityToVisit : cities) {
+			List<City> toVisitClone = new ArrayList<>(cities);
+			List<City> visitedClone = new ArrayList<>();
+			toVisitClone.remove(cityToVisit);
+			visitedClone.add(cityToVisit);
+			System.out.println("<" + cityToVisit.getName() + ">");
+			Thread thread = new Thread(new tspThread(toVisitClone, visitedClone));
+			thread.start();
+			//findBestRoute(toVisitClone, visitedClone);
+		}
+
+	}
+	public static void main(String[] args) {
+		new Traveling().start();
+	}
+
+	private static void buildDistancesMap(List<City> cities) {
+		 for (City from : cities) {
+			 for (City to : cities) {
+				 distances.put(Pair.of(from, to), from.distance(to));
+			 }
+		 }
+	}
+	
+
+	public static void findBestRoute(List<City> toVisit, List<City> visited) {
+		if (toVisit.isEmpty()) {
+			if (distance(visited) <= minimum) {
+				minimum = distance(visited);
+				System.out.format("%s %f%n", visited, minimum);
+			}
+			return;
+		}
+		for (City cityToVisit : toVisit) {
+			List<City> toVisitClone = new ArrayList<>(toVisit);
+			List<City> visitedClone = new ArrayList<>(visited);
+			toVisitClone.remove(cityToVisit);
+			visitedClone.add(cityToVisit);
+			findBestRoute(toVisitClone, visitedClone);
+		}
+	}
+
+	public static double distance(List<City> cities) {
+		double distance = 0.0D;
+		City city1 = null;
+		City city2 = null;
+		for (City city : cities) {
+			city1 = city2;
+			city2 = city;
+			if (city1 != null) {
+				distance += distances.get(Pair.of(city1, city2));
+			}
+		}
+		return distance;
+	}
+}
+
+class City {
+	private String name;
+	private int x;
+	private int y;
+
+	public double distance(City that) {
+		return Math.sqrt((this.x - that.x)*(this.x - that.x) + (this.y - that.y)*(this.y - that.y));
+	}
+
+	public City(String name, int x, int y) {
+		super();
+		this.name = name;
+		this.x = x;
+		this.y = y;
+	}
+
+	public String getName() {
+		return name;
+	}
+
+	public void setName(String name) {
+		this.name = name;
+	}
+
+	public int getX() {
+		return x;
+	}
+
+	public void setX(int x) {
+		this.x = x;
+	}
+
+	public int getY() {
+		return y;
+	}
+
+	public void setY(int y) {
+		this.y = y;
+	}
+
+	@Override
+	public String toString() {
+		return this.name;
+	}
+}
--- a/src/main/java/collatz/Collatz.java
+++ b/src/main/java/collatz/Collatz.java
@@ -0,0 +1,29 @@
+package collatz;
+import java.util.Comparator;
+import java.util.TreeSet;
+
+public class Collatz {
+
+    public static long collatz(long n) {
+        long steps = 0;
+        while (n > 1) {
+            steps++;
+            if (n % 2 == 0) {
+                n /= 2;
+            } else {
+                n *= 3;
+                n++;
+            }
+        }
+        return steps;
+    }
+
+    public static void main(String[] args) {
+
+
+        System.out.println(set);
+
+        System.out.println(collatz(27));
+    }
+}
+
--- a/src/main/java/fibo/Fibo.java
+++ b/src/main/java/fibo/Fibo.java
@@ -0,0 +1,18 @@
+package fibo;
+
+public class Fibo {
+
+	public static void main(String[] args) {
+		int N = 5212034;
+		double phi = (Math.sqrt(5) + 1)/2;
+		
+		int M = (int) (N/phi);
+		
+		do {
+			System.out.println(M);
+			M = N - M;
+			N = N - M;
+		} while (M > 0 && N > 0);
+		
+	}
+}
--- a/src/main/java/frobenius/FrobeniusNums.java
+++ b/src/main/java/frobenius/FrobeniusNums.java
@@ -0,0 +1,79 @@
+package frobenius;
+
+import java.util.Arrays;
+import java.util.Random;
+
+public class FrobeniusNums {
+
+    private static final int upperRange = 30;
+    private static final int toSearch = 129;
+    public static void main(String[] args) {
+        int[] numbers;
+        int frob = 0;
+        int frobMax = 0;
+
+        do {
+            numbers = new int[]{getRandomNumberInRange(3, upperRange), getRandomNumberInRange(3, upperRange), getRandomNumberInRange(3, upperRange)};
+            if (numbers[0] == numbers[1] || numbers[0] == numbers[2] || numbers[1] == numbers[2]) continue;
+            frob = frobenius(numbers);
+            if (frob > frobMax) {
+                frobMax = frob;
+                System.out.printf("%d: %s\n", frobMax, Arrays.toString(numbers));
+            }
+            if (frob == toSearch) {
+                System.out.printf("%d: %s\n", toSearch, Arrays.toString(numbers));
+            }
+        } while (frob != 10000);
+        System.out.println(Arrays.toString(numbers));
+    }
+
+    private static int getRandomNumberInRange(int min, int max) {
+
+        if (min >= max) {
+            throw new IllegalArgumentException("max must be greater than min");
+        }
+
+        Random r = new Random();
+        return r.nextInt((max - min) + 1) + min;
+    }
+
+    static int frobenius(int[] nums) {
+        int[] ns = new int[nums[0]];
+        Arrays.fill(ns, -1);
+        ns[0] = 0;
+        for (int i = 1; i < nums.length; i++) {
+            int d = gcd(nums[0], nums[i]);
+            for (int r = 0; r < d; r++) {
+                int n = -1;
+                if (r == 0)
+                    n = 0;
+                else {
+                    int q = r;
+                    while (q < nums[0]) {
+                        if (ns[q] != -1 && (ns[q] < n || n == -1))
+                            n = ns[q];
+                        q += d;
+                    }
+                }
+                if (n != -1)
+                    for (int j = 0; j < nums[0] / d; j++) {
+                        n += nums[i];
+                        int p = n % nums[0];
+                        if (ns[p] != -1 && (ns[p] < n || n == -1))
+                            n = ns[p];
+                        ns[p] = n;
+                    }
+            }
+        }
+        int max = 0;
+        for (int i = 0; i < nums[0]; i++)
+            if (ns[i] == -1 || ns[i] > max)
+                max = ns[i];
+        if (max == -1) return -1;
+        return max - nums[0];
+    }
+
+    static int gcd(int a, int b) {
+        return (b == 0) ? a : gcd(b, a % b);
+    }
+}
--- a/src/main/java/gsakpolygons/GSAKPolygons.java
+++ b/src/main/java/gsakpolygons/GSAKPolygons.java
@@ -0,0 +1,101 @@
+package gsakpolygons;
+
+import com.fasterxml.jackson.databind.DeserializationFeature;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import lombok.Builder;
+import org.locationtech.jts.geom.Coordinate;
+import org.locationtech.jts.geom.Geometry;
+import org.locationtech.jts.geom.MultiPolygon;
+import org.locationtech.jts.geom.Polygon;
+import org.wololo.geojson.Feature;
+import org.wololo.geojson.FeatureCollection;
+import org.wololo.jts2geojson.GeoJSONReader;
+
+import java.io.*;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+import java.util.Locale;
+import java.util.stream.Collectors;
+
+import static java.util.Collections.max;
+import static java.util.Collections.min;
+
+public class GSAKPolygons {
+    private static final String PREFIX = "D:\\Nextcloud\\Geocaching\\polygons\\";
+    private static final String OUTPUT_FOLDER = PREFIX + "new\\";
+    private static final boolean USE_NUMERIC_FILENAMES = true;
+    private static final String FILE_EXTENSION = ".txt";
+
+    private static final ObjectMapper objectMapper = new ObjectMapper().configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
+    private static final GeoJSONReader reader = new GeoJSONReader();
+
+    private static int fileCounter = 0;
+    private static List<MetaData> metadata = new ArrayList<>();
+
+    public static void main(String[] args) throws IOException {
+        FileInputStream inputStream = new FileInputStream(PREFIX + "Argentina_AL5.GeoJson");
+
+        FeatureCollection featureCollection = objectMapper.readValue(inputStream, FeatureCollection.class);
+
+        for (Feature feature : featureCollection.getFeatures()) {
+            String gsakName = (String) feature.getProperties().get("name");
+
+            MultiPolygon multiPolygon = (MultiPolygon) reader.read(feature.getGeometry());
+
+            if (multiPolygon.getNumGeometries() > 1) {
+                for (int geomNr = 0; geomNr < multiPolygon.getNumGeometries(); geomNr++) {
+                    Geometry geometry = multiPolygon.getGeometryN(geomNr);
+                    String fileName = (USE_NUMERIC_FILENAMES ? Integer.toString(++fileCounter) : gsakName + "_" + (geomNr + 1));
+                    processPolygon(geometry, gsakName, fileName);
+                }
+            } else {
+                Geometry geometry = multiPolygon.getGeometryN(0);
+                String fileName = (USE_NUMERIC_FILENAMES ? Integer.toString(++fileCounter) : gsakName);
+                processPolygon(geometry, gsakName, fileName);
+            }
+        }
+
+        try (Writer writer = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(OUTPUT_FOLDER + "meta.txt")))) {
+            for (MetaData meta : metadata) {
+                writer.write(meta.asCsv());
+                writer.write("\n");
+            }
+        }
+    }
+
+    private static void processPolygon(Geometry geometry, String gsakName, String fileName) throws IOException {
+        System.out.println(fileName);
+        try (Writer writer = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(OUTPUT_FOLDER + fileName + FILE_EXTENSION), "utf-8"))) {
+            writer.write("# GsakName=" + gsakName + "\n" +
+                    "# This Country polygon is based on data (c) OpenStreetMap contributors\n" +
+                    "# The OpenStreetMap data is made available under the Open Database License, see http://www.openstreetmap.org/copyright\n" +
+                    "# This polygon file is made available under the same Open Database License: http://opendatacommons.org/licenses/odbl/1.0/.\n");
+            for (Coordinate coordinate : geometry.getCoordinates()) {
+                writer.write(coordinate.y + "," + coordinate.x);
+                writer.write("\n");
+            }
+
+            Polygon boundingBox = (Polygon) geometry.getEnvelope();
+            Coordinate[] coordinates = boundingBox.getCoordinates();
+            List<Double> latitudes = Arrays.stream(coordinates).map(Coordinate::getY).collect(Collectors.toList());
+            List<Double> longitudes = Arrays.stream(coordinates).map(Coordinate::getX).collect(Collectors.toList());
+            metadata.add(MetaData.builder().fileName(fileName).gsakName(gsakName).minLat(min(latitudes)).maxLat(max(latitudes)).minLon(min(longitudes)).maxLon(max(longitudes)).build());
+        }
+    }
+}
+
+@Builder
+class MetaData {
+    // Filename, maxlat, minlat, maxlon, minlon, gsakname
+    private String fileName;
+    private double maxLat;
+    private double minLat;
+    private double maxLon;
+    private double minLon;
+    private String gsakName;
+
+    public String asCsv() {
+        return String.format(Locale.ROOT, "%s,%f,%f,%f,%f,%s", fileName, maxLat, minLat, maxLon, minLon, gsakName);
+    }
+}
--- a/src/main/java/hash/Dre1968.java
+++ b/src/main/java/hash/Dre1968.java
@@ -0,0 +1,27 @@
+package hash;
+
+import org.apache.commons.codec.digest.DigestUtils;
+
+public class Dre1968 {
+
+    private static final String template = "N52 %02d.%03d E005 %02d.%03d";
+    private static final String hashToFind = "4E77A87A1E3E9E362625A0A86508E1B8";
+    public static void main(String[] args) {
+//        String digest = DigestUtils.md5Hex("");
+        for (int nMin = 3; nMin <= 8; nMin++) {
+            for (int eMin = 49; eMin <= 57; eMin++) {
+                System.out.println(nMin + " " + eMin);
+                for (int nSec = 0; nSec <= 999; nSec++) {
+                    for (int eSec = 0; eSec <= 999; eSec++) {
+//                        System.out.println(String.format(template, nMin, nSec, eMin, eSec));
+                        if (hashToFind.equalsIgnoreCase(DigestUtils.md5Hex(String.format(template, nMin, nSec, eMin, eSec)))) {
+                            System.out.println(String.format(template, nMin, nSec, eMin, eSec));
+                            System.exit(0);
+
+                        }
+                    }
+                }
+            }
+        }
+    }
+}
--- a/src/main/java/hash/Hachee.java
+++ b/src/main/java/hash/Hachee.java
@@ -0,0 +1,506 @@
+package hash;
+
+import java.math.BigInteger;
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+import java.util.Arrays;
+import java.util.List;
+
+public class Hachee {
+
+	private static final List<String> aardappels = Arrays.asList(
+			"DORE",
+			"NIER",
+			"AGRIA",
+			"ALPHA",
+			"IRENE",
+			"KRIEL",
+			"MALTA",
+			"PATAT",
+			"POTER",
+			"RAPER",
+			"RODEN",
+			"ROTJE",
+			"GLORIA",
+			"LEGGER",
+			"ROOSJE",
+			"TOFFEL",
+			"BINTJE",
+			"FURORE",
+			"NICOLA",
+			"PIEPER",
+			"ROOIEN",
+			"ZANDER",
+			"AFKOKER",
+			"ASTARTE",
+			"ELEMENT",
+			"GLIMMER",
+			"SATURNA",
+			"BILDSTAR",
+			"HOORNTJE",
+			"BILTSTAR",
+			"DRIELING",
+			"PREMIERE",
+			"ROODNEUS",
+			"OPPERDOES",
+			"ARNHEMMER",
+			"CHARLOTTE",
+			"KEMPENAAR",
+			"PIMPERNEL",
+			"PREVALENT",
+			"PROMINENT",
+			"BEVELANDER",
+			"EERSTELING",
+			"NEGENWEKER",
+			"EIGENHEIMER",
+			"PAARSPETTEN",
+			"PAARSPITTEN",
+			"LEKKERLANDER");
+
+	private static final List<String> groentes = Arrays.asList(
+			"UI",
+			"LOF",
+			"SLA",
+			"BIET",
+			"EPPE",
+			"ERWT",
+			"MAIS",
+			"OKRA",
+			"PEUL",
+			"UIEN",
+			"BOON",
+			"KNOL",
+			"KOOL",
+			"MOES",
+			"PEEN",
+			"PREI",
+			"RAAP",
+			"BOSUI",
+			"KROOT",
+			"ATJAR",
+			"BONEN",
+			"IJSSLA",
+			"KUSSA",
+			"LATUW",
+			"RADIJS",
+			"TAHOE",
+			"TAUGE",
+			"FRISEE",
+			"KROTEN",
+			"MIELIE",
+			"RUCOLA",
+			"SAVOOI",
+			"SIEPEL",
+			"SJALOT",
+			"SPRUIT",
+			"WORTEL",
+			"BIETEN",
+			"DUNSEL",
+			"LINZEN",
+			"MOLSLA",
+			"PAKSOI",
+			"SAJOER",
+			"SALADE",
+			"SNIJSLA",
+			"TOMAAT",
+			"VENKEL",
+			"VETSLA",
+			"WITLOF",
+			"ZURING",
+			"BOLETEN",
+			"DOPERWT",
+			"KOOLSLA",
+			"LENTEUI",
+			"MEIKNOL",
+			"POMPOEN",
+			"RAMENAS",
+			"SNIJBIET",
+			"SNIJBOON",
+			"TOMATEN",
+			"ALFALFA",
+			"ANDIJVIE",
+			"ASPERGE",
+			"BIETJES",
+			"BOSPEEN",
+			"DOPPERS",
+			"KOPKOOL",
+			"KROPSLA",
+			"KRULSLA",
+			"LAMSOOR",
+			"MEIRAAP",
+			"PAPRIKA",
+			"RETTICH",
+			"SELDERIJ",
+			"SLABOON",
+			"TUINSLA",
+			"VELDSLA",
+			"VOEDSEL",
+			"WARMOES",
+			"WASBOON",
+			"WASPEEN",
+			"WITLOOF",
+			"AKKERSLA",
+			"ARTISJOK",
+			"ASPERGES",
+			"BIESLOOK",
+			"BOTERSLA",
+			"BUISKOOL",
+			"GROENLOF",
+			"KNOFLOOK",
+			"PEENTJES",
+			"PEULTJES",
+			"RAMMENAS",
+			"RODEKOOL",
+			"SPRUITEN",
+			"STOOFSLA",
+			"TUINKERS",
+			"VELDERWT",
+			"WORTELEN",
+			"BROCCOLI",
+			"KNOLRAAP",
+			"KOOLRAAP",
+			"KOOLRABI",
+			"KROPKOOL",
+			"PEULERWT",
+			"PORTULAK",
+			"RABARBER",
+			"SELDERIE",
+			"SLABONEN",
+			"SNIJBONEN",
+			"SPINAZIE",
+			"STOKBOON",
+			"STOKERWT",
+			"TUINBOON",
+			"ZUURKOOL",
+			"APPELMOES",
+			"BLOEMKOOL",
+			"FLAGEOLET",
+			"KAPUCIJNER",
+			"KASTANJES",
+			"KOMKOMMER",
+			"PASTINAAK",
+			"SEPARABEL",
+			"SPITSKOOL",
+			"TUINBONEN",
+			"WATERKERS",
+			"AUBERGINE",
+			"COURGETTE",
+			"DOPERWTEN",
+			"IJSBERGSLA",
+			"MOESKRUID",
+			"POSTELEIN",
+			"SLUITKOOL",
+			"SPRUITJES",
+			"VETSALADE",
+			"WITTEKOOL",
+			"AUBERGINES",
+			"CHAMPIGNON",
+			"DOPERWTJES",
+			"KAPUCIJNERS",
+			"KOOLSTRONK",
+			"PETERSELIE",
+			"RAAPSTELEN",
+			"STOOFPEREN",
+			"SUIKERMAIS",
+			"VENKELKNOL",
+			"WINTERPEEN",
+			"WORTELTJES",
+			"BOERENKOOL",
+			"GROENEKOOL",
+			"KABUISKOOL",
+			"KASANDIJVIE",
+			"KOUSENBAND",
+			"WINTERPREI",
+			"ARTISJOKKEN",
+			"CHAMPIGNONS",
+			"CITROENGRAS",
+			"FLESKALEBAS",
+			"KNOLSELDERIJ",
+			"PUNTPAPRIKA",
+			"SAVOOIEKOOL",
+			"SELDERIJKNOL",
+			"BLADSELDERIJ",
+			"SPERZIEBOON",
+			"BLADSPINAZIE",
+			"BLEEKSELDERIJ",
+			"CANTHARELLEN",
+			"CAYENNEPEPER",
+			"KNOLSELDERIE",
+			"SCHORSENEREN",
+			"SELDERIEKNOL",
+			"SELDERIEKOOL",
+			"SPERZIEBONEN",
+			"STOOFASPERGE",
+			"WINTERWORTEL",
+			"BLADSELDERIE",
+			"EIKENBLADSLA",
+			"SLEEPASPERGE",
+			"WINTERANDIJVIE",
+			"WINTERWORTELS",
+			"BLEEKSELDERIE",
+			"MUSKAATPOMPOEN",
+			"PRINSESSENBONEN",
+			"WINTERPOSTELEIN");
+	
+	private static final List<String> vlezen = Arrays.asList(
+			"KIP",
+			"HAM",
+			"BASK",
+			"HESP",
+			"SATE",
+			"BIEF",
+			"PATE",
+			"PORK",
+			"ROTI",
+			"STEW",
+			"TONG",
+			"ZULT",
+			"GYROS",
+			"KEBAK",
+			"ASPIC",
+			"BACON",
+			"KEBAB",
+			"SPIES",
+			"STEAK",
+			"WORST",
+			"PASTEI",
+			"POELET",
+			"SALAMI",
+			"BAKLAP",
+			"GEHAKT",
+			"HACHEE",
+			"HAMLAP",
+			"RAGOUT",
+			"REERUG",
+			"RIBLAP",
+			"ROLHAM",
+			"SAUCIJS",
+			"BEENHAM",
+			"BIEFLAP",
+			"CERVELA",
+			"GOULASH",
+			"LAMSRUG",
+			"PERSKOP",
+			"STOVERIJ",
+			"WORSTJE",
+			"GEBRAAD",
+			"KOTELET",
+			"LAMSRIB",
+			"PRESKOP",
+			"REEBOUT",
+			"RIBSTUK",
+			"ROLLADE",
+			"ROLPENS",
+			"ROSBIEF",
+			"SHOARMA",
+			"SLAVINK",
+			"SOEPKIP",
+			"SPEKLAP",
+			"TARTAAR",
+			"HAMLAPJE",
+			"METWORST",
+			"MOUSSAKA",
+			"OSSETONG",
+			"OSSOBUCO",
+			"PARMAHAM",
+			"ROOKSPEK",
+			"ROOMPATE",
+			"ROOMSATE",
+			"SJASLIEK",
+			"SPARERIB",
+			"TAGLIATA",
+			"ZWEZERIK",
+			"BERLINER",
+			"BIEFSTUK",
+			"ESCALOPE",
+			"FRIKADEL",
+			"KLAPSTUK",
+			"LAMSBOUT",
+			"NIERSTUK",
+			"NIERTJES",
+			"ROLLENDE",
+			"SAUCISSE",
+			"SHOWARMA",
+			"STOOFLAP",
+			"ANDOUILLE",
+			"BALKENBRIJ",
+			"CASSEROLE",
+			"CASSOULET",
+			"KALFSTONG",
+			"KIPBURGER",
+			"LAMSZADEL",
+			"LEVERKAAS",
+			"OSSENTONG",
+			"EENDVOGEL",
+			"ENTRECOTE",
+			"FRICASSEE",
+			"GALANTINE",
+			"GEHAKTBAL",
+			"HAMBURGER",
+			"HOOFDKAAS",
+			"KARBONADE",
+			"KATENSPEK",
+			"KNAKWORST",
+			"OSSENHAAS",
+			"PLOKWORST",
+			"ROASTBEEF",
+			"ROOKWORST",
+			"RUNDERLAP",
+			"RUNDVLEES",
+			"SCHNITZEL",
+			"SPARERIBS",
+			"SUDDERLAP",
+			"SUKADELAP",
+			"TOURNEDOS",
+			"UIERBOORD",
+			"BLINDEVINK",
+			"BLOEDWORST",
+			"EENDENBOUT",
+			"FRICANDEAU",
+			"HAZENPEPER",
+			"KALFSLAPJE",
+			"LAMSGEHAKT",
+			"LAMSOESTER",
+			"LEVERWORST",
+			"PEKELVLEES",
+			"PEPERSTEAK",
+			"SUKADESTUK",
+			"WILDPASTEI",
+			"BOERENPATE",
+			"BRAADVLEES",
+			"BRAADWORST",
+			"KIPROLLADE",
+			"LENDENSTUK",
+			"OSSENVLEES",
+			"REEGEBRAAD",
+			"RUNDERHAAS",
+			"STOOFLAPJE",
+			"GEHAKTBROOD",
+			"LAMSSCHOTEL",
+			"LEVERPASTEI",
+			"TONGENWORST",
+			"VOGELNESTJE",
+			"CASSELERRIB",
+			"KALFSGEHAKT",
+			"KALFSOESTER",
+			"KASSELERRIB",
+			"LAMSKOTELET",
+			"RUNDERLEVER",
+			"SCHAPENBOUT",
+			"KALFSROLLADE",
+			"KIPSCHNITZEL",
+			"RIBKARBONADE",
+			"GEHAKTBALLEN",
+			"KALFSKOTELET",
+			"RUNDERGEHAKT",
+			"VARKENSLEVER",
+			"VARKENSVLEES",
+			"BOOMSTAMMETJE",
+			"CHATEAUBRIAND",
+			"LENDEBIEFSTUK",
+			"GEHAKTSCHOTEL",
+			"HAASKARBONADE",
+			"LAMSKARBONADE",
+			"RUNDERROLLADE",
+			"VARKENSGEHAKT",
+			"VARKENSOESTER",
+			"KALFSFRICANDEAU",
+			"WIENERSCHNITZEL",
+			"PAARDENROOKVLEES",
+			"STRUISVOGELBIEFSTUK");
+	
+	private static final List<String> sauzen = Arrays.asList(
+			"AIOLI",
+			"ANDALOUSESAUS",
+			"BEARNAISESAUS",
+			"BECHAMELSAUS",
+			"BLACKWELLSAUS",
+			"BOLOGNESESAUS",
+			"CHUTNEY",
+			"CHIMICHURRI",
+			"COCKTAILSAUS",
+			"CURRY",
+			"CURRYKETCHUP",
+			"DIPSAUS",
+			"DRESSING",
+			"FRITESSAUS",
+			"GUACAMOLE",
+			"GROENE SAUS",
+			"HARISSA",
+			"HOLLANDAISESAUS",
+			"CHINESE HOISINSAUS",
+			"HUMMUS",
+			"JOPPIESAUS",
+			"KAASSAUS",
+			"KETJAP",
+			"KNOFLOOKSAUS",
+			"MADERASAUS",
+			"MAMMOETSAUS",
+			"MANGOCHUTNEY",
+			"MAYONAISE",
+			"MOJO",
+			"MOSTERD",
+			"OESTERSAUS",
+			"PESTO",
+			"PINDASAUS",
+			"PICCALILLY",
+			"PIRIPIRI",
+			"ROUX",
+			"SALSA",
+			"SALSA VERDE",
+			"SAMBAL",
+			"SAMOERAISAUS",
+			"SATESAUS",
+			"ROQUEFORTSAUS",
+			"STOOFVLEESSAUS",
+			"STROGANOFFSAUS",
+			"TABASCO",
+			"TAHINI",
+			"TAPENADE",
+			"TARTAARSAUS",
+			"TOMATENKETCHUP",
+			"TOMATENSAUS",
+			"TOMOTTOSAUS",
+			"TZATZIKI",
+			"VINAIGRETTE",
+			"VISSAUS",
+			"VLAMMENSAUS",
+			"VLEESJUS",
+			"WHISKYSAUS",
+			"WITTE SAUS",
+			"WORCESTERSAUS",
+			"ZULUSAUS");
+	
+	private static final String GOAL = "818028943427c1157af2aa007a4ab802cb53312a";
+	
+	public static void main(String[] args) throws NoSuchAlgorithmException {
+		System.out.println(str2hash("92.111.40.218 AARDAPPEL GROENTE VLEES SAUS"));
+		
+		for (String aardappel : aardappels) {
+			System.out.println("@" + aardappel);
+			for (String groente : groentes) {
+				for (String vlees : vlezen) {
+					for (String saus : sauzen) {
+						if (str2hash(String.format("92.111.40.218 %s %s %s %s", aardappel, groente, vlees, saus)).equals(GOAL)) {
+							System.out.println(aardappel);
+							System.out.println(groente);
+							System.out.println(vlees);
+							System.out.println(saus);
+						}
+					}
+				}
+			}
+		}
+	}
+	
+	private static String str2hash(String s) throws NoSuchAlgorithmException {
+//		MessageDigest md5 = MessageDigest.getInstance("SHA256");
+//		md5.update(s.getBytes());
+		//byte[] digest = md5.digest();
+//		return String.format("%032x", new BigInteger(1, md5.digest()));
+		
+		byte[] digest = Ripemd160.getHash(s.getBytes());
+		return String.format("%032x", new BigInteger(1, digest));
+		
+	}
+}
--- a/src/main/java/hash/Ripemd160.java
+++ b/src/main/java/hash/Ripemd160.java
@@ -0,0 +1,157 @@
+/* 
+ * Bitcoin cryptography library
+ * Copyright (c) Project Nayuki
+ * 
+ * https://www.nayuki.io/page/bitcoin-cryptography-library
+ * https://github.com/nayuki/Bitcoin-Cryptography-Library
+ */
+
+package hash;
+
+import static java.lang.Integer.rotateLeft;
+import java.util.Arrays;
+import java.util.Objects;
+
+
+/**
+ * Computes the RIPEMD-160 hash of an array of bytes. Not instantiable.
+ */
+public final class Ripemd160 {
+	
+	private static final int BLOCK_LEN = 64;  // In bytes
+	
+	
+	
+	/*---- Static functions ----*/
+	
+	/**
+	 * Computes and returns a 20-byte (160-bit) hash of the specified binary message.
+	 * Each call will return a new byte array object instance.
+	 * @param msg the message to compute the hash of
+	 * @return a 20-byte array representing the message's RIPEMD-160 hash
+	 * @throws NullPointerException if the message is {@code null}
+	 */
+	public static byte[] getHash(byte[] msg) {
+		// Compress whole message blocks
+		Objects.requireNonNull(msg);
+		int[] state = {0x67452301, 0xEFCDAB89, 0x98BADCFE, 0x10325476, 0xC3D2E1F0};
+		int off = msg.length / BLOCK_LEN * BLOCK_LEN;
+		compress(state, msg, off);
+		
+		// Final blocks, padding, and length
+		byte[] block = new byte[BLOCK_LEN];
+		System.arraycopy(msg, off, block, 0, msg.length - off);
+		off = msg.length % block.length;
+		block[off] = (byte)0x80;
+		off++;
+		if (off + 8 > block.length) {
+			compress(state, block, block.length);
+			Arrays.fill(block, (byte)0);
+		}
+		long len = (long)msg.length << 3;
+		for (int i = 0; i < 8; i++)
+			block[block.length - 8 + i] = (byte)(len >>> (i * 8));
+		compress(state, block, block.length);
+		
+		// Int32 array to bytes in little endian
+		byte[] result = new byte[state.length * 4];
+		for (int i = 0; i < result.length; i++)
+			result[i] = (byte)(state[i / 4] >>> (i % 4 * 8));
+		return result;
+	}
+	
+	
+	
+	/*---- Private functions ----*/
+	
+	private static void compress(int[] state, byte[] blocks, int len) {
+		if (len % BLOCK_LEN != 0)
+			throw new IllegalArgumentException();
+		for (int i = 0; i < len; i += BLOCK_LEN) {
+			
+			// Message schedule
+			int[] schedule = new int[16];
+			for (int j = 0; j < BLOCK_LEN; j++)
+				schedule[j / 4] |= (blocks[i + j] & 0xFF) << (j % 4 * 8);
+			
+			// The 80 rounds
+			int al = state[0], ar = state[0];
+			int bl = state[1], br = state[1];
+			int cl = state[2], cr = state[2];
+			int dl = state[3], dr = state[3];
+			int el = state[4], er = state[4];
+			for (int j = 0; j < 80; j++) {
+				int temp;
+				temp = rotateLeft(al + f(j, bl, cl, dl) + schedule[RL[j]] + KL[j / 16], SL[j]) + el;
+				al = el;
+				el = dl;
+				dl = rotateLeft(cl, 10);
+				cl = bl;
+				bl = temp;
+				temp = rotateLeft(ar + f(79 - j, br, cr, dr) + schedule[RR[j]] + KR[j / 16], SR[j]) + er;
+				ar = er;
+				er = dr;
+				dr = rotateLeft(cr, 10);
+				cr = br;
+				br = temp;
+			}
+			int temp = state[1] + cl + dr;
+			state[1] = state[2] + dl + er;
+			state[2] = state[3] + el + ar;
+			state[3] = state[4] + al + br;
+			state[4] = state[0] + bl + cr;
+			state[0] = temp;
+		}
+	}
+	
+	
+	private static int f(int i, int x, int y, int z) {
+		assert 0 <= i && i < 80;
+		if (i < 16) return x ^ y ^ z;
+		if (i < 32) return (x & y) | (~x & z);
+		if (i < 48) return (x | ~y) ^ z;
+		if (i < 64) return (x & z) | (y & ~z);
+		return x ^ (y | ~z);
+	}
+	
+	
+	/*---- Class constants ----*/
+	
+	private static final int[] KL = {0x00000000, 0x5A827999, 0x6ED9EBA1, 0x8F1BBCDC, 0xA953FD4E};  // Round constants for left line
+	private static final int[] KR = {0x50A28BE6, 0x5C4DD124, 0x6D703EF3, 0x7A6D76E9, 0x00000000};  // Round constants for right line
+	
+	private static final int[] RL = {  // Message schedule for left line
+		 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15,
+		 7,  4, 13,  1, 10,  6, 15,  3, 12,  0,  9,  5,  2, 14, 11,  8,
+		 3, 10, 14,  4,  9, 15,  8,  1,  2,  7,  0,  6, 13, 11,  5, 12,
+		 1,  9, 11, 10,  0,  8, 12,  4, 13,  3,  7, 15, 14,  5,  6,  2,
+		 4,  0,  5,  9,  7, 12,  2, 10, 14,  1,  3,  8, 11,  6, 15, 13};
+	
+	private static final int[] RR = {  // Message schedule for right line
+		 5, 14,  7,  0,  9,  2, 11,  4, 13,  6, 15,  8,  1, 10,  3, 12,
+		 6, 11,  3,  7,  0, 13,  5, 10, 14, 15,  8, 12,  4,  9,  1,  2,
+		15,  5,  1,  3,  7, 14,  6,  9, 11,  8, 12,  2, 10,  0,  4, 13,
+		 8,  6,  4,  1,  3, 11, 15,  0,  5, 12,  2, 13,  9,  7, 10, 14,
+		12, 15, 10,  4,  1,  5,  8,  7,  6,  2, 13, 14,  0,  3,  9, 11};
+	
+	private static final int[] SL = {  // Left-rotation for left line
+		11, 14, 15, 12,  5,  8,  7,  9, 11, 13, 14, 15,  6,  7,  9,  8,
+		 7,  6,  8, 13, 11,  9,  7, 15,  7, 12, 15,  9, 11,  7, 13, 12,
+		11, 13,  6,  7, 14,  9, 13, 15, 14,  8, 13,  6,  5, 12,  7,  5,
+		11, 12, 14, 15, 14, 15,  9,  8,  9, 14,  5,  6,  8,  6,  5, 12,
+		 9, 15,  5, 11,  6,  8, 13, 12,  5, 12, 13, 14, 11,  8,  5,  6};
+	
+	private static final int[] SR = {  // Left-rotation for right line
+		 8,  9,  9, 11, 13, 15, 15,  5,  7,  7,  8, 11, 14, 14, 12,  6,
+		 9, 13, 15,  7, 12,  8,  9, 11,  7,  7, 12,  7,  6, 15, 13, 11,
+		 9,  7, 15, 11,  8,  6,  6, 14, 12, 13,  5, 14, 13, 13,  7,  5,
+		15,  5,  8, 11, 14, 14,  6, 14,  6,  9, 12,  9, 12,  5, 15,  8,
+		 8,  5, 12,  9, 12,  5, 14,  6,  8, 13,  6,  5, 15, 13, 11, 11};
+	
+	
+	
+	/*---- Miscellaneous ----*/
+	
+	private Ripemd160() {}  // Not instantiable
+	
+}
--- a/src/main/java/lingbeek/LingbeekBirthday.java
+++ b/src/main/java/lingbeek/LingbeekBirthday.java
@@ -0,0 +1,110 @@
+package lingbeek;
+
+public class LingbeekBirthday {
+	
+	public static void main(String[] args) {
+		puzzel2();
+	}
+	
+	public static void puzzel2() {
+		String getal = "718221388361140459273845060881935892202463276395185767703202931844979553404160205473165154807716047721360387093977836573461869078903866177517609401066995933056937641429822696075026042708998059408245652909668617234963230159004523361922445118939939425246591630178718041250790393911485448198886968520292419143016465413331107690345523662227756770090925212522853663683587115889316348412482481435850444765959813967931241192116530004379144859416555126822428355054939181176327053123262208427234806432042801083591095061910485620434178736995513637382640868397650863502002563325892782309465718819728901067970753170885152774767519324699535246704946474908543771629786109206017292416056868587459999802797209566648129905865161668379298914522843344050237568463975430764997329482907540684058754472128156434536314672907436279703636811174767549267019613087844658170533886775690229572515615825038183957272309738331226296504597797142318758354872756609064068357178635668850213496389401828224429501408463336955800619499038431637344375259571562615451815648323843802309260072491322883789721070700813804934145478570772226861124445569426679549892906002113429532043386726315834027769929259745736978918570066127364472548758413479889126261314951579365554009611739580747480367882483804688653102749852533773280287182213883611404592738450608819358922024632763951857677032029318449795534041602054731651548077160477213603870939778365734618690789038661775176094010669959330569376414298226960750260427089980594082456529096686172349632301590045233619224451189399394252465916301787180412507903939114854481988869685202924191430164654133311076903455236622277567700909252125228536636835871158893163484124824814358504447659598139679312411921165300043791448594165551268224283550549391811763270531232622084272348064320428010835910950619104856204341787369955136373826408683976508635020025633258927823094657188197289010679707531708851527747675193246995352467049464749085437716297861092060172924160568685874599998027972095666481299058651616683792989145228433440502375684639754307649973294829075406840587544721281564345363146729074362797036368111747675492670196130878446581705338867756902295725156158250381839572723097383312262965045977971423187583548727566090640683571786356688502134963894018282244295014084633369558006194990384316373443752595715626154518156483238438023092600724913228837897210707008138049341454785707722268611244455694266795498929";
+		getal += "0600211342953204338672631583402776992925974573697891857006612736447254875841347988912626131495157936555400961173958074748036788248380468865310274985253377328028718221388361140459273845060881935892202463276395185767703202931844979553404160205473165154807716047721360387093977836573461869078903866177517609401066995933056937641429822696075026042708998059408245652909668617234963230159004523361922445118939939425246591630178718041250790393911485448198886968520292419143016465413331107690345523662227756770090925212522853663683587115889316348412482481435850444765959813967931241192116530004379144859416555126822428355054939181176327053123262208427234806432042801083591095061910485620434178736995513637382640868397650863502002563325892782309465718819728901067970753170885152774767519324699535246704946474908543771629786109206017292416056868587459999802797209566648129905865161668379298914522843344050237568463975430764997329482907540684058754472128156434536314672907436279703636811174767549267019613087844658170533886775690229572515615825038183957272309738331226296504597797142318758354872756609064068357178635668850213496389401828224429501408463336955800619499038431637344375259571562615451815648323843802309260072491322883789721070700813804934145478570772226861124445569426679549892906002113429532043386726315834027769929259745736978918570066127364472548758413479889126261314951579365554009611739580747480367882483804688653102749852533773280287182213883611404592738450608819358922024632763951857677032029318449795534041602054731651548077160477213603870939778365734618690789038661775176094010669959330569376414298226960750260427089980594082456529096686172349632301590045233619224451189399394252465916301787180412507903939114854481988869685202924191430164654133311076903455236622277567700909252125228536636835871158893163484124824814358504447659598139679312411921165300043791448594165551268224283550549391811763270531232622084272348064320428010835910950619104856204341787369955136373826408683976508635020025633258927823094657188197289010679707531708851527747675193246995352467049464749085437716297861092060172924160568685874599998027972095666481299058651616683792989145228433440502375684639754307649973294829075406840587544721281564345363146729074362797036368111747675492670196130878446581705338867756902295725156158250381839572723097383312262965045977971423187583548727566090640683571786356688502134963894018282";
+		getal += "2442950140846333695580061949903843163734437525957156261545181564832384380230926007249132288378972107070081380493414547857077222686112444556942667954989290600211342953204338672631583402776992925";
+
+		char[] chars = getal.toCharArray();
+		long max = 0;
+		for (int i=0; i < (chars.length - 12); i++) {
+			long prod = 1;
+			for (int j=0; j<13; j++) {
+				prod *= (chars[i+j] - '0');
+				if (prod > max) max = prod;
+			}
+			System.out.println(prod);
+		}
+		
+		System.out.println(max);
+	}
+	public static void puzzel1() {
+		
+		int[][] grid = {
+				{34,9,22,97,58,34,9,40,44,74,4,4,7,68,42,32,40,77,83,8},
+				{49,49,99,40,37,83,38,47,60,87,37,40,98,45,69,48,4,46,62,0},
+				{83,49,53,75,41,79,34,29,95,73,40,67,45,88,50,5,49,35,56,64},
+				{42,70,94,25,4,60,33,42,69,24,68,46,3,52,46,73,57,2,56,93},
+				{22,53,36,73,43,67,65,99,43,92,56,14,22,40,40,28,66,55,35,80},
+				{24,47,52,60,99,5,44,32,44,74,55,45,68,56,84,20,54,37,32,40},
+				{52,28,83,28,64,25,67,30,96,58,40,67,49,44,70,66,38,58,64,70},
+				{67,56,22,68,2,62,32,20,94,65,94,59,65,8,40,93,66,49,94,23},
+				{24,84,48,4,66,75,99,26,97,37,70,68,96,86,34,88,54,89,65,72},
+				{23,56,25,9,74,0,76,44,20,44,54,34,50,63,55,97,54,53,55,94},
+				{68,37,45,28,22,74,53,67,34,93,25,80,4,62,36,34,9,45,46,92},
+				{36,59,34,42,96,54,53,47,44,48,88,24,30,37,41,24,56,29,84,47},
+				{86,46,14,77,54,73,89,7,4,41,44,57,41,60,23,48,43,44,37,48},
+				{39,80,83,68,4,94,47,69,28,75,92,35,86,42,37,77,4,89,44,40},
+				{4,42,8,85,83,54,99,36,7,97,47,52,36,26,26,79,55,27,98,66},
+				{88,56,68,87,47,62,20,72,5,46,55,67,46,44,32,52,65,95,45,69},
+				{4,42,36,75,58,24,59,33,24,94,72,38,8,46,29,52,40,62,76,56},
+				{20,69,56,43,72,50,25,88,54,62,99,69,82,67,49,84,74,44,56,36},
+				{20,75,54,29,68,53,90,3,74,53,49,73,48,86,83,36,25,47,4,14},
+				{3,70,44,73,85,43,44,69,36,82,55,48,63,15,42,3,99,29,67,48}
+		};
+		int max = 0, result;
+
+		for (int row = 0; row < grid.length; row++ ) {
+			for (int col = 0; col < grid[row].length; col++) {
+				if (col < 17) {
+					result = grid[row][col] * grid [row][col+1] * grid[row][col+2] * grid[row][col+3];
+					if (result > max) {
+						System.out.println("["+row+"]["+col+"] 1");
+						max = result;
+					}
+				}
+				if (row < 17) {
+					result = grid[row][col] * grid [row+1][col] * grid[row+2][col] * grid[row+3][col];
+					if (result > max) {
+						System.out.println("["+row+"]["+col+"] 2 " + grid[row][col]);
+						max = result;
+					}
+				}
+				
+				if (col < 17 && row > 2) {
+					result = grid[row][col] * grid [row-1][col+1] * grid[row-2][col+2] * grid[row-3][col+3];
+					if (result > max) {
+						System.out.println("["+row+"]["+col+"] 3");
+						max = result;
+					}
+				}
+
+				if (col < 17 && row < 17) {
+					result = grid[row][col] * grid [row+1][col+1] * grid[row+2][col+2] * grid[row+3][col+3];
+					if (result > max) {
+						System.out.println("["+row+"]["+col+"] 4");
+						max = result;
+					}
+				}
+
+				if (col > 2 && row < 17) {
+					result = grid[row][col] * grid [row+1][col-1] * grid[row+2][col-2] * grid[row+3][col-3];
+					if (result > max) {
+						System.out.println("["+row+"]["+col+"] 5");
+						max = result;
+					}
+				}
+
+				if (col > 2 && row > 2) {
+					result = grid[row][col] * grid [row-1][col-1] * grid[row-2][col-2] * grid[row-3][col-3];
+					if (result > max) {
+						System.out.println("["+row+"]["+col+"]");
+						max = result;
+					}
+				}
+
+				//System.out.print(grid[row][col]);
+			}
+			//System.out.println();
+		}
+		
+		System.out.println(max);
+
+	}
+}
--- a/src/main/java/logistics/LogisticsPuzzle.java
+++ b/src/main/java/logistics/LogisticsPuzzle.java
@@ -0,0 +1,196 @@
+package logistics;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+import java.util.Random;
+
+//interface Node {
+//	boolean visited = false;
+//	void addNode(Node node, int distance);
+//	Map<Node, Integer> getNodes();
+//	String getName();
+//}
+
+abstract class Node {
+	private String name;
+	private Map<Node, Integer> connectedNodes = new HashMap<>();
+	private boolean visited;
+	
+	public void addNode(Node node, int distance) {
+		connectedNodes.put(node, distance);
+	}
+	
+	public Map<Node, Integer> getNodes() {
+		return connectedNodes;
+	}
+	
+	public boolean isVisited() {
+		return visited;
+	}
+
+	public void setVisited(boolean visited) {
+		this.visited = visited;
+	}
+
+	public String getName() {
+		return name;
+	}
+
+	public void setName(String name) {
+		this.name = name;
+	}
+	
+	void enter(Car car) {
+		this.visited = true;
+	};
+	
+}
+
+class Stop extends Node {
+
+	Stop(String name) {
+		this.setName(name);
+	}
+}
+
+class GasStation extends Node {
+	private int gasAdded;
+	
+	GasStation(String name, int gasAdded) {
+		this.setName(name);
+		this.gasAdded = gasAdded;
+	}
+	
+	@Override
+	public void enter(Car car) {
+		super.enter(car);
+		car.addGas(this.gasAdded);
+	}
+}
+
+class Car {
+	private int fuel;
+	private int distance = 0;
+	private Node position;
+	
+	public void addGas(int gasAdded) {
+		this.fuel += gasAdded;
+	}
+
+	public void driveTo(Node node, int distance) {
+		this.position = node;
+		this.fuel -= distance;
+		this.distance += distance;
+		node.enter(this);
+	}
+
+	public int getFuel() {
+		return fuel;
+	}
+
+	public void setFuel(int fuel) {
+		this.fuel = fuel;
+	}
+
+	public Node getPosition() {
+		return position;
+	}
+
+	public void setPosition(Node position) {
+		this.position = position;
+	}
+
+	public int getDistance() {
+		return distance;
+	}
+	
+	
+	
+}
+
+public class LogisticsPuzzle {
+	static Car car = new Car();
+	static List<Node> allNodes;
+	public static void main(String[] args) {
+		car.setFuel(30);
+//		Node s1 = new Stop("s1");
+//		Node s2 = new Stop("s2");
+//		Node s3 = new Stop("s3");
+//		Node g1 = new GasStation("g1", 30);
+//		s1.addNode(s2, 10);
+//		s1.addNode(s3, 5);
+//		s2.addNode(s3, 20);
+//		s3.addNode(s1, 5);
+//		s3.addNode(g1, 10);
+//		g1.addNode(s2, 12);
+		
+		Node node;
+		for (Integer n = 1; n <= 10; n++) {
+			if (new Random().nextInt(5) == 0) {
+				node = new GasStation(n.toString(), 20 + new Random().nextInt(25));
+			} else {
+				node = new Stop(n.toString());
+			}
+			allNodes.add(node);
+		}
+		
+		//allNodes = Arrays.asList(new Node[] { s1, s2, s3, g1} );
+		
+//		car.driveTo(s1, 0);
+
+		System.out.println("Position     Fuel       Dist     Nodes");
+		
+		printState();
+		
+		do {
+			Map<Node,Integer> nodes = car.getPosition().getNodes();
+			Iterator<Node> iterator = nodes.keySet().iterator();
+			
+			while (iterator.hasNext()) {
+				/*Node*/ node = iterator.next();
+				if (nodes.get(node) > car.getFuel()) {
+					iterator.remove();
+				}
+			}
+			
+			if (nodes.isEmpty()) {
+				System.out.println("Geen benzine meer.");
+				break;
+			}
+			
+			Random random = new Random();
+			List<Node> keys = new ArrayList<Node>(nodes.keySet());
+			Node nextStop = keys.get( random.nextInt(keys.size()) );
+			int distance = nodes.get(nextStop);
+					
+			car.driveTo(nextStop, distance);
+			printState();
+			if (allNodesVisited()) {
+				System.out.println("Klaar");
+				break;
+			}
+		} while (true);
+	}
+	
+	static boolean allNodesVisited() {
+		boolean allVisited = true;
+		for (Node node : allNodes) {
+//			System.out.println(node.getName() + node.isVisited());
+			allVisited = allVisited && node.isVisited();
+		}
+		return allVisited;
+		
+	}
+	
+	static void printState() {
+		System.out.print(car.getPosition().getName() + "           " + car.getFuel() + "          " + car.getDistance() + "          ");
+		for (Node node : car.getPosition().getNodes().keySet()) {
+			System.out.print(node.getName() + " ");
+		}
+		System.out.println();
+	};
+}
--- a/src/main/java/numbersquare/NumberSquarePuzzle.java
+++ b/src/main/java/numbersquare/NumberSquarePuzzle.java
@@ -0,0 +1,132 @@
+package numbersquare;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Random;
+
+enum Direction {
+	UP, LEFT, DOWN, RIGHT;
+}
+
+public class NumberSquarePuzzle {
+
+	public static final int SIZE = 7;
+	
+	public static void main(String[] args) {
+		
+		int [][] square = {
+//				{4,2,2,3,3},
+//				{2,2,2,2,2},
+//				{3,2,2,2,2},
+//				{1,2,3,2,3},
+//				{3,2,2,2,0}
+				{6,3,2,4,6,2,5},
+				{3,5,2,4,4,4,1},
+				{3,3,2,3,3,4,2},
+				{3,4,1,2,2,5,3},
+				{4,4,4,2,3,2,4},
+				{2,5,4,2,3,2,5},
+				{3,5,2,1,4,4,0}
+		};
+		
+//		6 (0,0) => 3 (6,0)
+//		3 (6,0) => 1 (6,3)
+//		1 (6,3) => 2 (6,2)
+//		2 (6,2) => 4 (4,2)
+//		4 (4,2) => 2 (0,2)
+//		2 (0,2) => 2 (2,2)
+//		2 (2,2) => 3 (2,0)
+//		3 (2,0) => 2 (5,0)
+//		2 (5,0) => 4 (5,2)
+//		4 (5,2) => 2 (1,2)
+//		2 (1,2) => 4 (1,4)
+//		4 (1,4) => 3 (1,0)
+//		3 (1,0) => 4 (4,0)
+//		4 (4,0) => 3 (4,4)
+//		3 (4,4) => 4 (4,1)
+//		4 (4,1) => 2 (4,5)
+//		2 (4,5) => 4 (6,5)
+//		4 (6,5) => 5 (6,1)
+//		5 (6,1) => 0 (6,6)
+		
+//		6 (0,0) => 3 (6,0)
+//		3 (6,0) => 1 (6,3)
+//		1 (6,3) => 2 (6,2)
+//		2 (6,2) => 4 (4,2)
+//		4 (4,2) => 2 (0,2)
+//		2 (0,2) => 2 (2,2)
+//		2 (2,2) => 3 (2,0)
+//		3 (2,0) => 2 (5,0)
+//		2 (5,0) => 4 (5,2)
+//		4 (5,2) => 2 (1,2)
+//		2 (1,2) => 3 (1,0)
+//		3 (1,0) => 4 (4,0)
+//		4 (4,0) => 3 (4,4)
+//		3 (4,4) => 4 (4,1)
+//		4 (4,1) => 2 (4,5)
+//		2 (4,5) => 4 (2,5)
+//		4 (2,5) => 4 (6,5)
+//		4 (6,5) => 5 (6,1)
+//		5 (6,1) => 0 (6,6)
+		
+		boolean [][] visited;
+		
+		int posRow;
+		int posCol;
+		int curVal;
+		
+		int attempt = 0;
+		
+		do {
+			attempt++;
+			posRow = 0;
+			posCol = 0;
+			List<Direction> directions;
+			visited = new boolean[SIZE][SIZE];
+			
+			do {
+				directions = new ArrayList<>();
+				visited[posRow][posCol] = true;
+				
+				curVal = square[posRow][posCol];
+				
+				if ((posCol + curVal) < SIZE) {
+					directions.add(Direction.RIGHT);
+				}
+				if ((posCol - curVal) >= 0) {
+					directions.add(Direction.LEFT);
+				}
+				if ((posRow + curVal) < SIZE) {
+					directions.add(Direction.DOWN);
+				}
+				if ((posRow - curVal) >= 0) {
+					directions.add(Direction.UP);
+				}
+				
+				Direction direction = directions.get(new Random().nextInt(directions.size()));
+		
+				System.out.print(curVal + " (" + posRow + "," + posCol + ") => ");
+		
+				if (direction == Direction.RIGHT) {
+					posCol += curVal;
+				}
+				if (direction == Direction.LEFT) {
+					posCol -= curVal;
+				}
+				if (direction == Direction.DOWN) {
+					posRow += curVal;
+				}
+				if (direction == Direction.UP) {
+					posRow -= curVal;
+				}
+				
+				System.out.println(square[posRow][posCol] + " (" + posRow + "," + posCol + ")");
+				
+				if (visited[posRow][posCol]) {
+					System.out.println("Visited " + attempt);
+					break;
+				}
+			} while (posRow != (SIZE - 1) || posCol != (SIZE - 1));
+		} while (posRow != (SIZE - 1) || posCol != (SIZE - 1));
+	}
+}
--- a/src/main/java/polygons/PolygonConverter.java
+++ b/src/main/java/polygons/PolygonConverter.java
@@ -0,0 +1,61 @@
+package polygons;
+
+import com.fasterxml.jackson.databind.DeserializationFeature;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import org.locationtech.jts.geom.Coordinate;
+import org.locationtech.jts.geom.Geometry;
+import org.locationtech.jts.geom.MultiPolygon;
+import org.wololo.geojson.Feature;
+import org.wololo.geojson.FeatureCollection;
+import org.wololo.jts2geojson.GeoJSONReader;
+
+import java.io.*;
+
+public class PolygonConverter {
+    private static final String prefix = "D:\\Nextcloud\\Geocaching\\polygons\\";
+    private static final String outputFolder = prefix + "new\\";
+    private static final ObjectMapper objectMapper = new ObjectMapper().configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
+    private static final GeoJSONReader reader = new GeoJSONReader();
+    private static final boolean USE_NUMERIC_FILENAMES = true;
+    private static int FILE_COUNTER = 0;
+
+    public static void main(String[] args) throws IOException {
+        FileInputStream inputStream = new FileInputStream(prefix + "russia_counties.GeoJson");
+
+        FeatureCollection featureCollection = objectMapper.readValue(inputStream, FeatureCollection.class);
+
+        for (Feature feature : featureCollection.getFeatures()) {
+            String baseName = (String) feature.getProperties().get("name");
+
+            MultiPolygon multiPolygon = (MultiPolygon) reader.read(feature.getGeometry());
+            if (multiPolygon.getNumGeometries() > 1) {
+                for (int geomNr = 0; geomNr < multiPolygon.getNumGeometries(); geomNr++) {
+                    Geometry geometry = multiPolygon.getGeometryN(geomNr);
+                    String fileName = (USE_NUMERIC_FILENAMES ? Integer.toString(++FILE_COUNTER) : baseName + "_" + (geomNr + 1)) + ".txt";
+                    processPolygon(geometry, baseName, fileName);
+                }
+            } else {
+                Geometry geometry = multiPolygon.getGeometryN(0);
+                String fileName = (USE_NUMERIC_FILENAMES ? Integer.toString(++FILE_COUNTER) : baseName) + ".txt";
+                processPolygon(geometry, baseName, fileName);
+            }
+        }
+    }
+
+    private static void processPolygon(Geometry geometry, String name, String fileName) throws IOException {
+        System.out.println(fileName);
+        try (Writer writer = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(outputFolder + fileName), "utf-8"))) {
+            writer.write("# GsakName=" + name + "\n" +
+                    "# This Country polygon is based on data (c) OpenStreetMap contributors\n" +
+                    "# The OpenStreetMap data is made available under the Open Database License, see http://www.openstreetmap.org/copyright\n" +
+                    "# This polygon file is made available under the same Open Database License: http://opendatacommons.org/licenses/odbl/1.0/.\n");
+//            Geometry reducedPolygon = reducePolygon(polygon);
+            //geometry.getBoundary()
+            for (Coordinate coordinate : geometry.getCoordinates()) {
+                writer.write(coordinate.y + "," + coordinate.x);
+                writer.write("\n");
+            }
+        }
+    }
+}
+
--- a/src/main/java/setGame/Card.java
+++ b/src/main/java/setGame/Card.java
@@ -0,0 +1,76 @@
+package setGame;
+
+class Card {
+	P1 p1;
+	P2 p2;
+	P3 p3;
+	P4 p4;
+	P5 p5;
+
+	public P1 getP1() {
+		return p1;
+	}
+
+	public void setP1(P1 p1) {
+		this.p1 = p1;
+	}
+
+	public P2 getP2() {
+		return p2;
+	}
+
+	public void setP2(P2 p2) {
+		this.p2 = p2;
+	}
+
+	public P3 getP3() {
+		return p3;
+	}
+
+	public void setP3(P3 p3) {
+		this.p3 = p3;
+	}
+	
+
+	public P4 getP4() {
+		return p4;
+	}
+
+	public void setP4(P4 p4) {
+		this.p4 = p4;
+	}
+
+	public P5 getP5() {
+		return p5;
+	}
+
+	public void setP5(P5 p5) {
+		this.p5 = p5;
+	}
+
+	public Card(P1 p1, P2 p2, P3 p3, P4 p4, P5 p5) {
+		super();
+		this.p1 = p1;
+		this.p2 = p2;
+		this.p3 = p3;
+		this.p4 = p4;
+		this.p5 = p5;
+	}
+
+	@Override
+	public boolean equals(Object o) {
+		Card that = (Card) o;
+		return this.p1 == that.p1 && this.p2 == that.p2 && this.p3 == that.p3 && this.p4 == that.p4 && this.p5 == that.p5;
+	}
+	@Override
+	public int hashCode() {
+		return 1;
+	}
+	@Override
+	public String toString() {
+		return p1 + " " + p2 + " " + p3 + " " + p4 + " " + p5;
+	}
+	public static Card randomCard() {
+		return new Card(P1.randomP1(), P2.randomP2(), P3.randomP3(), P4.randomP4(), P5.randomP5());
+	}
+}
--- a/src/main/java/setGame/P1.java
+++ b/src/main/java/setGame/P1.java
@@ -0,0 +1,18 @@
+package setGame;
+
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+import java.util.Random;
+
+enum P1 {
+	A1, A2, A3, A4, A5;
+
+	private static final List<P1> VALUES = Collections.unmodifiableList(Arrays.asList(values()));
+	private static final int SIZE = VALUES.size();
+	private static final Random RANDOM = new Random();
+
+	public static P1 randomP1() {
+		return VALUES.get(RANDOM.nextInt(SIZE));
+	}
+}
--- a/src/main/java/setGame/P2.java
+++ b/src/main/java/setGame/P2.java
@@ -0,0 +1,18 @@
+package setGame;
+
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+import java.util.Random;
+
+enum P2 {
+	B1, B2, B3, B4, B5;
+
+	private static final List<P2> VALUES = Collections.unmodifiableList(Arrays.asList(values()));
+	private static final int SIZE = VALUES.size();
+	private static final Random RANDOM = new Random();
+
+	public static P2 randomP2() {
+		return VALUES.get(RANDOM.nextInt(SIZE));
+	}
+}
--- a/src/main/java/setGame/P3.java
+++ b/src/main/java/setGame/P3.java
@@ -0,0 +1,18 @@
+package setGame;
+
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+import java.util.Random;
+
+enum P3 {
+	C1, C2, C3, C4, C5;
+
+	private static final List<P3> VALUES = Collections.unmodifiableList(Arrays.asList(values()));
+	private static final int SIZE = VALUES.size();
+	private static final Random RANDOM = new Random();
+
+	public static P3 randomP3() {
+		return VALUES.get(RANDOM.nextInt(SIZE));
+	}
+}
--- a/src/main/java/setGame/P4.java
+++ b/src/main/java/setGame/P4.java
@@ -0,0 +1,18 @@
+package setGame;
+
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+import java.util.Random;
+
+enum P4 {
+	D1, D2, D3, D4, D5;
+
+	private static final List<P4> VALUES = Collections.unmodifiableList(Arrays.asList(values()));
+	private static final int SIZE = VALUES.size();
+	private static final Random RANDOM = new Random();
+
+	public static P4 randomP4() {
+		return VALUES.get(RANDOM.nextInt(SIZE));
+	}
+}
--- a/src/main/java/setGame/P5.java
+++ b/src/main/java/setGame/P5.java
@@ -0,0 +1,18 @@
+package setGame;
+
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+import java.util.Random;
+
+enum P5 {
+	E1, E2, E3, E4, E5;
+
+	private static final List<P5> VALUES = Collections.unmodifiableList(Arrays.asList(values()));
+	private static final int SIZE = VALUES.size();
+	private static final Random RANDOM = new Random();
+
+	public static P5 randomP5() {
+		return VALUES.get(RANDOM.nextInt(SIZE));
+	}
+}
--- a/src/main/java/setGame/SearchResult.java
+++ b/src/main/java/setGame/SearchResult.java
@@ -0,0 +1,14 @@
+package setGame;
+
+import java.util.List;
+import java.util.Set;
+
+class SearchResult {
+	public Set<Card> cards;
+	public List<Set<Card>> sets;
+	public SearchResult(Set<Card> cards, List<Set<Card>> sets) {
+		super();
+		this.cards = cards;
+		this.sets = sets;
+	}
+}
--- a/src/main/java/setGame/SetGame.java
+++ b/src/main/java/setGame/SetGame.java
@@ -0,0 +1,232 @@
+package setGame;
+
+import java.util.List;
+import java.util.Set;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+import javax.sound.sampled.AudioFormat;
+import javax.sound.sampled.AudioSystem;
+import javax.sound.sampled.Clip;
+import javax.sound.sampled.LineEvent;
+import javax.sound.sampled.LineListener;
+import javax.sound.sampled.LineUnavailableException;
+import javax.swing.Timer;
+
+import java.util.HashSet;
+import java.awt.event.ActionEvent;
+import java.awt.event.ActionListener;
+import java.nio.ByteBuffer;
+import java.util.ArrayList;
+
+public class SetGame {
+	
+	private static final int SET_SIZE = 5;
+
+	public static void main(String[] args) {
+		SearchResult sr;
+		int size;
+		int record = 85;
+		do {
+			sr = tryRandom();
+			
+			size = sr.cards.size();
+			if (size >= record && sr.sets.size() == 1) {
+				record = size;
+				try {
+					beep(3000, 200);
+				} catch (InterruptedException | LineUnavailableException e) {
+					e.printStackTrace();
+				}
+				System.out.println(size + " " + sr.sets.size());
+				for (Card card : sr.cards) {
+					System.out.println(card);
+				}
+//				System.out.println("Met " + sr.sets.size() + " sets.");
+				System.out.println(sr.sets);
+			}
+		} while (true);
+		
+	}
+	
+	private static SearchResult tryRandom() {
+		Set<Card> cards = new HashSet<>();
+//		int sets = 0;
+		do {
+			cards.add(Card.randomCard());
+		} while (cards.size() < SET_SIZE);
+		do {
+			cards.add(Card.randomCard());
+			List<Set<Card>> sets = sets(cards, false);
+			if (sets.size() > 0) {
+				return new SearchResult(cards, sets);
+			}
+		} while (true);
+		
+	}
+	
+	private static List<Set<Card>> sets(Set<Card> cards, boolean debug) {
+
+		List<Set<Card>> sets = new ArrayList<>();
+		
+		for (int i = 0; i < cards.size() - 4; i++) {
+			for (int j = i + 1; j < cards.size() - 3; j++) {
+				for (int k = j + 1; k < cards.size() - 2; k++) {
+					for (int l = k + 1; l < cards.size() - 1; l++) {
+						for (int m = l + 1; m < cards.size(); m++) {
+
+							boolean result = false;
+							List<Card> cardsList = new ArrayList<>(cards);
+							Set<P1> p1s = new HashSet<P1>();
+							p1s.add(cardsList.get(i).getP1());
+							p1s.add(cardsList.get(j).getP1());
+							p1s.add(cardsList.get(k).getP1());
+							p1s.add(cardsList.get(l).getP1());
+							p1s.add(cardsList.get(m).getP1());
+							
+							Set<P2> p2s = new HashSet<P2>();
+							p2s.add(cardsList.get(i).getP2());
+							p2s.add(cardsList.get(j).getP2());
+							p2s.add(cardsList.get(k).getP2());
+							p2s.add(cardsList.get(l).getP2());
+							p2s.add(cardsList.get(m).getP2());
+
+							Set<P3> p3s = new HashSet<P3>();
+							p3s.add(cardsList.get(i).getP3());
+							p3s.add(cardsList.get(j).getP3());
+							p3s.add(cardsList.get(k).getP3());
+							p3s.add(cardsList.get(l).getP3());
+							p3s.add(cardsList.get(m).getP3());
+
+							Set<P4> p4s = new HashSet<P4>();
+							p4s.add(cardsList.get(i).getP4());
+							p4s.add(cardsList.get(j).getP4());
+							p4s.add(cardsList.get(k).getP4());
+							p4s.add(cardsList.get(l).getP4());
+							p4s.add(cardsList.get(m).getP4());
+	
+							Set<P5> p5s = new HashSet<P5>();
+							p5s.add(cardsList.get(i).getP5());
+							p5s.add(cardsList.get(j).getP5());
+							p5s.add(cardsList.get(k).getP5());
+							p5s.add(cardsList.get(l).getP5());
+							p5s.add(cardsList.get(m).getP5());
+							
+							result |= (p1s.size() >= 2 && p1s.size() <= (SET_SIZE - 1));
+							result |= (p2s.size() >= 2 && p2s.size() <= (SET_SIZE - 1));
+							result |= (p3s.size() >= 2 && p3s.size() <= (SET_SIZE - 1));
+							result |= (p4s.size() >= 2 && p4s.size() <= (SET_SIZE - 1));
+							result |= (p5s.size() >= 2 && p5s.size() <= (SET_SIZE - 1));
+							
+	/*						System.out.println("Kaarten " + i+","+j+","+k+","+l+":");
+							System.out.println(cardsList.get(i));
+							System.out.println(cardsList.get(j));
+							System.out.println(cardsList.get(k));
+							System.out.println(cardsList.get(l));
+							System.out.println("Verschillende P1s: " + p1s.size());
+							System.out.println("Verschillende P2s: " + p2s.size());
+							System.out.println("Verschillende P3s: " + p3s.size());
+							System.out.println("Verschillende P4s: " + p4s.size());
+	*/						
+							if (result == false) {
+								sets.add(Stream.of(cardsList.get(i), cardsList.get(j), cardsList.get(k), cardsList.get(l), cardsList.get(m)).collect(Collectors.toSet()));
+								if (debug) {
+									System.out.println(cardsList.get(i) + " " + i);
+									System.out.println(cardsList.get(j) + " " + j);
+									System.out.println(cardsList.get(k) + " " + k);
+									System.out.println(cardsList.get(l) + " " + l);
+									System.out.println(cardsList.get(m) + " " + m);
+									System.out.println();
+								}
+							}
+						}
+					}
+				}
+			}
+		}
+		
+		return sets;
+	}
+	
+	public static void beep(double freq, final double millis) throws InterruptedException, LineUnavailableException {
+
+        final Clip clip = AudioSystem.getClip();
+        /**
+         * AudioFormat of the reclieved clip. Probably you can alter it
+         * someway choosing proper Line.
+         */
+        AudioFormat af = clip.getFormat();
+
+        /**
+         * We assume that encoding uses signed shorts. Probably we could
+         * make this code more generic but who cares.
+         */
+        if (af.getEncoding() != AudioFormat.Encoding.PCM_SIGNED){
+            throw new UnsupportedOperationException("Unknown encoding");
+        }
+
+        if (af.getSampleSizeInBits() != 16) {
+            System.err.println("Weird sample size.  Dunno what to do with it.");
+            return;
+        }
+
+        /**
+         * Number of bytes in a single frame
+         */
+        int bytesPerFrame = af.getFrameSize();
+        /**
+         * Number of frames per second
+         */
+        double fps = af.getFrameRate();
+        /**
+         * Number of frames during the clip .
+         */
+        int frames = (int)(fps * (millis / 1000));
+
+        /**
+         * Data
+         */
+        ByteBuffer data = ByteBuffer.allocate(frames * bytesPerFrame);
+
+        /**
+         * We will emit sinus, which needs to be scaled so it has proper
+         * frequency --- here is the scaling factor.
+         */
+        double freqFactor = (Math.PI / 2) * freq / fps;
+        /**
+         * This sinus must also be scaled so it fills short.
+         */
+        double ampFactor = Short.MAX_VALUE;
+
+        short sample;
+
+        for (int frame = 0; frame < frames; frame++) {
+            sample = (short) (ampFactor * Math.sin(frame * freqFactor));
+            data.putShort(sample);
+        }
+        clip.open(af, data.array(), 0, data.position());
+
+        // This is so Clip releases its data line when done.  Otherwise at 32 clips it breaks.
+        clip.addLineListener(new LineListener() {
+            @Override
+            public void update(LineEvent event) {
+                if (event.getType() == LineEvent.Type.START) {
+                    Timer t = new Timer((int)millis + 1, new ActionListener() {
+                        @Override
+                        public void actionPerformed(ActionEvent e) {
+                            clip.close();
+                        }
+                    });
+                    t.setRepeats(false);
+                    t.start();
+                }
+            }
+        });
+        clip.start();
+
+        Thread.sleep((long)millis);
+
+
+
+    }
+}
--- a/src/main/java/stamps/Stamps.java
+++ b/src/main/java/stamps/Stamps.java
@@ -0,0 +1,81 @@
+package stamps;
+
+import org.apache.commons.lang3.RandomUtils;
+import com.google.common.collect.Sets;
+
+import java.util.*;
+
+public class Stamps {
+
+    private static final int SUM = 100;
+    private static final int CHOOSE = 5;
+    private static final int UPPER_STAMP = 36;
+    private static final int LOWER_STAMP = 4;
+    private static final int TOTAL_STAMPS = 5;
+
+
+    public static void main(String[] args) {
+        for (int j = 0; j < 1000; j++) {
+            TreeSet<Integer> stamps = null;
+            for (int i = 0; i < 1000; i++) {
+                stamps = poging();
+                if (stamps != null) break;
+            }
+
+            SortedMap<Integer, Integer> sums = new TreeMap<>();
+
+            int minSum = 1000;
+            int maxSum = 0;
+
+            for (Set<Integer> set : Sets.combinations(stamps, CHOOSE)) {
+                int sumSet = set.stream().mapToInt(Integer::intValue).sum();
+                int sum = sums.containsKey(sumSet) ? sums.get(sumSet) : 0;
+                sums.put(sumSet, sum + 1);
+            }
+
+            int sumsBeforeGoal = 0;
+            int sumsAfterGoal = 0;
+
+            for (int s : sums.keySet()) {
+                if (s < SUM) sumsBeforeGoal += sums.get(s);
+                if (s > SUM) sumsAfterGoal += sums.get(s);
+            }
+
+            if (sumsBeforeGoal > 100 && sumsAfterGoal > 100) {
+                System.out.println(stamps);
+                System.out.println(sumsBeforeGoal + " << " + SUM + " >> " + sumsAfterGoal);
+            }
+        }
+    }
+
+    private static TreeSet<Integer> poging() {
+        var stamps = Sets.newHashSet(8, 12, 22, 23, 35);
+        var triedStamps = new HashSet<Integer>();
+
+        for (int i = 0; i < TOTAL_STAMPS; i++) {
+            int newStamp;
+            do {
+                if (triedStamps.size() == (UPPER_STAMP - LOWER_STAMP + 1)) {
+//                    System.out.println("Mislukt");
+                    return null;
+                }
+                newStamp = RandomUtils.nextInt(LOWER_STAMP, UPPER_STAMP + 1);
+                triedStamps.add(newStamp);
+            } while (stamps.contains(newStamp) || !testNewStamp(stamps, newStamp));
+            stamps.add(newStamp);
+//            System.out.println(newStamp + " toegevoegd.");
+        }
+        TreeSet<Integer> sortStamps = new TreeSet<>(stamps);
+        return sortStamps;
+    }
+
+    private static boolean testNewStamp(Set<Integer> stamps, int newStamp) {
+        for (Set<Integer> set : Sets.combinations(stamps, CHOOSE - 1)) {
+            if (set.stream().mapToInt(Integer::intValue).sum() + newStamp == SUM) {
+//                System.out.println(newStamp + " valt af.");
+                return false;
+            }
+        }
+        return true;
+    }
+}
--- a/src/main/java/stamps/Stamps2.java
+++ b/src/main/java/stamps/Stamps2.java
@@ -0,0 +1,99 @@
+package stamps;
+
+import com.google.common.collect.Sets;
+import org.apache.commons.lang3.RandomUtils;
+import org.apache.commons.math3.util.CombinatoricsUtils;
+
+import java.util.*;
+
+public class Stamps2 {
+
+    private static final int SUM = 100;
+    private static final int CHOOSE = 6;
+    private static final int UPPER_STAMP = 40;
+    private static final int LOWER_STAMP = 2;
+    private static final int TOTAL_STAMPS = 11;
+    private static final int THRESHOLD = (int) ((CombinatoricsUtils.binomialCoefficient(TOTAL_STAMPS, CHOOSE) / 2) * 0.5);
+
+
+    public static void main(String[] args) {
+        outerloop:
+        for (int j = 0; j < 50000000; j++) {
+            TreeSet<Integer> stamps = null;
+            stamps = poging();
+
+            SortedMap<Integer, Integer> sums = new TreeMap<>();
+
+            int minSum = 1000;
+            int maxSum = 0;
+            Set<Integer> solutionSet = null;
+
+            for (Set<Integer> set : Sets.combinations(stamps, CHOOSE)) {
+                int sumSet = set.stream().mapToInt(Integer::intValue).sum();
+                int sum = sums.containsKey(sumSet) ? sums.get(sumSet) : 0;
+                sums.put(sumSet, sum + 1);
+                if (sumSet == SUM) {
+                    solutionSet = new TreeSet<Integer>(set);
+                }
+            }
+
+            int sumsBeforeGoal = 0;
+            int sumsAfterGoal = 0;
+
+            for (int s : sums.keySet()) {
+                if (s < SUM) sumsBeforeGoal += sums.get(s);
+                if (s > SUM) sumsAfterGoal += sums.get(s);
+            }
+
+            boolean success = true;
+
+
+
+            if (success && sumsBeforeGoal > THRESHOLD && sumsAfterGoal > THRESHOLD && sums.containsKey(SUM) && sums.get(SUM) == 1) {
+
+
+                for (int choose = 1; choose <= TOTAL_STAMPS; choose++) {
+                    if (choose == CHOOSE) {
+                        continue;
+                    }
+                    for (Set<Integer> set : Sets.combinations(stamps, choose)) {
+                        int sumSet = set.stream().mapToInt(Integer::intValue).sum();
+                        if (sumSet == SUM) {
+                            success = false;
+//                            System.out.println(set + " spoils the party.");
+                            continue outerloop;
+                        }
+                    }
+                }
+
+                System.out.println(stamps);
+                System.out.println(sumsBeforeGoal + " << " + SUM + " >> " + sumsAfterGoal);
+                System.out.println("Solution: " + solutionSet);
+                System.out.println();
+
+
+            }
+        }
+    }
+
+    //private static int threshold()
+
+    private static TreeSet<Integer> poging() {
+        var stamps = new HashSet<Integer>();
+        var triedStamps = new HashSet<Integer>();
+
+        for (int i = 0; i < TOTAL_STAMPS; i++) {
+            int newStamp;
+            do {
+
+                newStamp = RandomUtils.nextInt(LOWER_STAMP, UPPER_STAMP + 1);
+                triedStamps.add(newStamp);
+            } while (stamps.contains(newStamp));
+            stamps.add(newStamp);
+
+        }
+        TreeSet<Integer> sortStamps = new TreeSet<>(stamps);
+        return sortStamps;
+    }
+
+}
--- a/src/main/java/tsp/City.java
+++ b/src/main/java/tsp/City.java
@@ -0,0 +1,47 @@
+/*
+* City.java
+* Models a city
+*/
+
+package tsp;
+
+public class City {
+    int x;
+    int y;
+    
+    // Constructs a randomly placed city
+    public City(){
+        this.x = (int)(Math.random()*200);
+        this.y = (int)(Math.random()*200);
+    }
+    
+    // Constructs a city at chosen x, y location
+    public City(int x, int y){
+        this.x = x;
+        this.y = y;
+    }
+    
+    // Gets city's x coordinate
+    public int getX(){
+        return this.x;
+    }
+    
+    // Gets city's y coordinate
+    public int getY(){
+        return this.y;
+    }
+    
+    // Gets the distance to given city
+    public double distanceTo(City city){
+        int xDistance = Math.abs(getX() - city.getX());
+        int yDistance = Math.abs(getY() - city.getY());
+        double distance = Math.sqrt( (xDistance*xDistance) + (yDistance*yDistance) );
+        
+        return distance;
+    }
+    
+    @Override
+    public String toString(){
+        return getX()+", "+getY();
+    }
+}
--- a/src/main/java/tsp/GA.java
+++ b/src/main/java/tsp/GA.java
@@ -0,0 +1,120 @@
+/*
+* GA.java
+* Manages algorithms for evolving population
+*/
+
+package tsp;
+
+public class GA {
+
+    /* GA parameters */
+    private static final double mutationRate = 0.015;
+    private static final int tournamentSize = 5;
+    private static final boolean elitism = true;
+
+    // Evolves a population over one generation
+    public static Population evolvePopulation(Population pop) {
+        Population newPopulation = new Population(pop.populationSize(), false);
+
+        // Keep our best individual if elitism is enabled
+        int elitismOffset = 0;
+        if (elitism) {
+            newPopulation.saveTour(0, pop.getFittest());
+            elitismOffset = 1;
+        }
+
+        // Crossover population
+        // Loop over the new population's size and create individuals from
+        // Current population
+        for (int i = elitismOffset; i < newPopulation.populationSize(); i++) {
+            // Select parents
+            Tour parent1 = tournamentSelection(pop);
+            Tour parent2 = tournamentSelection(pop);
+            // Crossover parents
+            Tour child = crossover(parent1, parent2);
+            // Add child to new population
+            newPopulation.saveTour(i, child);
+        }
+
+        // Mutate the new population a bit to add some new genetic material
+        for (int i = elitismOffset; i < newPopulation.populationSize(); i++) {
+            mutate(newPopulation.getTour(i));
+        }
+
+        return newPopulation;
+    }
+
+    // Applies crossover to a set of parents and creates offspring
+    public static Tour crossover(Tour parent1, Tour parent2) {
+        // Create new child tour
+        Tour child = new Tour();
+
+        // Get start and end sub tour positions for parent1's tour
+        int startPos = (int) (Math.random() * parent1.tourSize());
+        int endPos = (int) (Math.random() * parent1.tourSize());
+
+        // Loop and add the sub tour from parent1 to our child
+        for (int i = 0; i < child.tourSize(); i++) {
+            // If our start position is less than the end position
+            if (startPos < endPos && i > startPos && i < endPos) {
+                child.setCity(i, parent1.getCity(i));
+            } // If our start position is larger
+            else if (startPos > endPos) {
+                if (!(i < startPos && i > endPos)) {
+                    child.setCity(i, parent1.getCity(i));
+                }
+            }
+        }
+
+        // Loop through parent2's city tour
+        for (int i = 0; i < parent2.tourSize(); i++) {
+            // If child doesn't have the city add it
+            if (!child.containsCity(parent2.getCity(i))) {
+                // Loop to find a spare position in the child's tour
+                for (int ii = 0; ii < child.tourSize(); ii++) {
+                    // Spare position found, add city
+                    if (child.getCity(ii) == null) {
+                        child.setCity(ii, parent2.getCity(i));
+                        break;
+                    }
+                }
+            }
+        }
+        return child;
+    }
+
+    // Mutate a tour using swap mutation
+    private static void mutate(Tour tour) {
+        // Loop through tour cities
+        for(int tourPos1=0; tourPos1 < tour.tourSize(); tourPos1++){
+            // Apply mutation rate
+            if(Math.random() < mutationRate){
+                // Get a second random position in the tour
+                int tourPos2 = (int) (tour.tourSize() * Math.random());
+
+                // Get the cities at target position in tour
+                City city1 = tour.getCity(tourPos1);
+                City city2 = tour.getCity(tourPos2);
+
+                // Swap them around
+                tour.setCity(tourPos2, city1);
+                tour.setCity(tourPos1, city2);
+            }
+        }
+    }
+
+    // Selects candidate tour for crossover
+    private static Tour tournamentSelection(Population pop) {
+        // Create a tournament population
+        Population tournament = new Population(tournamentSize, false);
+        // For each place in the tournament get a random candidate tour and
+        // add it
+        for (int i = 0; i < tournamentSize; i++) {
+            int randomId = (int) (Math.random() * pop.populationSize());
+            tournament.saveTour(i, pop.getTour(randomId));
+        }
+        // Get the fittest tour
+        Tour fittest = tournament.getFittest();
+        return fittest;
+    }
+}
--- a/src/main/java/tsp/Population.java
+++ b/src/main/java/tsp/Population.java
@@ -0,0 +1,53 @@
+/*
+* Population.java
+* Manages a population of candidate tours
+*/
+
+package tsp;
+
+public class Population {
+
+    // Holds population of tours
+    Tour[] tours;
+
+    // Construct a population
+    public Population(int populationSize, boolean initialise) {
+        tours = new Tour[populationSize];
+        // If we need to initialise a population of tours do so
+        if (initialise) {
+            // Loop and create individuals
+            for (int i = 0; i < populationSize(); i++) {
+                Tour newTour = new Tour();
+                newTour.generateIndividual();
+                saveTour(i, newTour);
+            }
+        }
+    }
+    
+    // Saves a tour
+    public void saveTour(int index, Tour tour) {
+        tours[index] = tour;
+    }
+    
+    // Gets a tour from population
+    public Tour getTour(int index) {
+        return tours[index];
+    }
+
+    // Gets the best tour in the population
+    public Tour getFittest() {
+        Tour fittest = tours[0];
+        // Loop through individuals to find fittest
+        for (int i = 1; i < populationSize(); i++) {
+            if (fittest.getFitness() <= getTour(i).getFitness()) {
+                fittest = getTour(i);
+            }
+        }
+        return fittest;
+    }
+
+    // Gets population size
+    public int populationSize() {
+        return tours.length;
+    }
+}
--- a/src/main/java/tsp/TSP_GA.java
+++ b/src/main/java/tsp/TSP_GA.java
@@ -0,0 +1,71 @@
+/*
+* TSP_GA.java
+* Create a tour and evolve a solution
+*/
+
+package tsp;
+
+public class TSP_GA {
+
+    public static void main(String[] args) {
+
+
+        // Create and add our cities
+        City city = new City(60, 200);
+        TourManager.addCity(city);
+        City city2 = new City(180, 200);
+        TourManager.addCity(city2);
+        City city3 = new City(80, 180);
+        TourManager.addCity(city3);
+        City city4 = new City(140, 180);
+        TourManager.addCity(city4);
+        City city5 = new City(20, 160);
+        TourManager.addCity(city5);
+        City city6 = new City(100, 160);
+        TourManager.addCity(city6);
+        City city7 = new City(200, 160);
+        TourManager.addCity(city7);
+        City city8 = new City(140, 140);
+        TourManager.addCity(city8);
+        City city9 = new City(40, 120);
+        TourManager.addCity(city9);
+        City city10 = new City(100, 120);
+        TourManager.addCity(city10);
+        City city11 = new City(180, 100);
+        TourManager.addCity(city11);
+        City city12 = new City(60, 80);
+        TourManager.addCity(city12);
+        City city13 = new City(120, 80);
+        TourManager.addCity(city13);
+        City city14 = new City(180, 60);
+        TourManager.addCity(city14);
+        City city15 = new City(20, 40);
+        TourManager.addCity(city15);
+        City city16 = new City(100, 40);
+        TourManager.addCity(city16);
+        City city17 = new City(200, 40);
+        TourManager.addCity(city17);
+        City city18 = new City(20, 20);
+        TourManager.addCity(city18);
+        City city19 = new City(60, 20);
+        TourManager.addCity(city19);
+        City city20 = new City(160, 20);
+        TourManager.addCity(city20);
+
+        // Initialize population
+        Population pop = new Population(50, true);
+        System.out.println("Initial distance: " + pop.getFittest().getDistance());
+
+        // Evolve population for 100 generations
+        pop = GA.evolvePopulation(pop);
+        for (int i = 0; i < 10000; i++) {
+            pop = GA.evolvePopulation(pop);
+        }
+
+        // Print final results
+        System.out.println("Finished");
+        System.out.println("Final distance: " + pop.getFittest().getDistance());
+        System.out.println("Solution:");
+        System.out.println(pop.getFittest());
+    }
+}
--- a/src/main/java/tsp/Tour.java
+++ b/src/main/java/tsp/Tour.java
@@ -0,0 +1,105 @@
+/*
+* Tour.java
+* Stores a candidate tour
+*/
+
+package tsp;
+
+import java.util.ArrayList;
+import java.util.Collections;
+
+public class Tour{
+
+    // Holds our tour of cities
+    private ArrayList tour = new ArrayList<City>();
+    // Cache
+    private double fitness = 0;
+    private int distance = 0;
+    
+    // Constructs a blank tour
+    public Tour(){
+        for (int i = 0; i < TourManager.numberOfCities(); i++) {
+            tour.add(null);
+        }
+    }
+    
+    public Tour(ArrayList tour){
+        this.tour = tour;
+    }
+
+    // Creates a random individual
+    public void generateIndividual() {
+        // Loop through all our destination cities and add them to our tour
+        for (int cityIndex = 0; cityIndex < TourManager.numberOfCities(); cityIndex++) {
+          setCity(cityIndex, TourManager.getCity(cityIndex));
+        }
+        // Randomly reorder the tour
+        Collections.shuffle(tour);
+    }
+
+    // Gets a city from the tour
+    public City getCity(int tourPosition) {
+        return (City)tour.get(tourPosition);
+    }
+
+    // Sets a city in a certain position within a tour
+    public void setCity(int tourPosition, City city) {
+        tour.set(tourPosition, city);
+        // If the tours been altered we need to reset the fitness and distance
+        fitness = 0;
+        distance = 0;
+    }
+    
+    // Gets the tours fitness
+    public double getFitness() {
+        if (fitness == 0) {
+            fitness = 1/(double)getDistance();
+        }
+        return fitness;
+    }
+    
+    // Gets the total distance of the tour
+    public int getDistance(){
+        if (distance == 0) {
+            int tourDistance = 0;
+            // Loop through our tour's cities
+            for (int cityIndex=0; cityIndex < tourSize(); cityIndex++) {
+                // Get city we're travelling from
+                City fromCity = getCity(cityIndex);
+                // City we're travelling to
+                City destinationCity;
+                // Check we're not on our tour's last city, if we are set our
+                // tour's final destination city to our starting city
+                if(cityIndex+1 < tourSize()){
+                    destinationCity = getCity(cityIndex+1);
+                }
+                else{
+                    destinationCity = getCity(0);
+                }
+                // Get the distance between the two cities
+                tourDistance += fromCity.distanceTo(destinationCity);
+            }
+            distance = tourDistance;
+        }
+        return distance;
+    }
+
+    // Get number of cities on our tour
+    public int tourSize() {
+        return tour.size();
+    }
+    
+    // Check if the tour contains a city
+    public boolean containsCity(City city){
+        return tour.contains(city);
+    }
+    
+    @Override
+    public String toString() {
+        String geneString = "|";
+        for (int i = 0; i < tourSize(); i++) {
+            geneString += getCity(i)+"|";
+        }
+        return geneString;
+    }
+}
--- a/src/main/java/tsp/TourManager.java
+++ b/src/main/java/tsp/TourManager.java
@@ -0,0 +1,29 @@
+/*
+* TourManager.java
+* Holds the cities of a tour
+*/
+
+package tsp;
+
+import java.util.ArrayList;
+
+public class TourManager {
+
+    // Holds our cities
+    private static ArrayList destinationCities = new ArrayList<City>();
+
+    // Adds a destination city
+    public static void addCity(City city) {
+        destinationCities.add(city);
+    }
+    
+    // Get a city
+    public static City getCity(int index){
+        return (City)destinationCities.get(index);
+    }
+    
+    // Get the number of destination cities
+    public static int numberOfCities(){
+        return destinationCities.size();
+    }
+}