Inverse graph method was added

src/Task9.java

-import java.io.*;
+import java.io.BufferedReader;
+import java.io.FileOutputStream;
+import java.io.FileReader;
+import java.io.IOException;
 import java.nio.ByteBuffer;
 import java.nio.channels.FileChannel;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.util.*;
-import java.util.stream.Stream;
 
 public class Task9 {
   public static void main(String[] args) {
 
     Graph g = null;
     try {
-      g = new Graph("noder.txt");
+      g = new Graph("noder Iceland.txt");
     } catch (IOException e) {
       e.printStackTrace();
     }
-    Objects.requireNonNull(g).loadEdges("kanter.txt");
-    //g.loadNodes("noder.txt");
-    /*int startNumber = 0;
+    Objects.requireNonNull(g).loadEdges("kanterIceland.txt");
+    int startNumber = 0;
     List<Edge> edges = g.getShortestPath(0,3);
     System.out.println(startNumber);
     for (Edge edge: edges) {
       System.out.println(edge.getDestination());
     }
     System.out.println("----------------------- Dijkstra Done --------------------------------");
-    g.readNodeInformation("interessepkt.txt");
+    g.loadNodes("noder Iceland.txt");
+    g.readNodeInformation("interessepktIceland.txt");
     Node[] listOfPlaces = g.getListOfPlaces(0,Byte.parseByte("2"),Byte.parseByte("8"));
     for(Node node: listOfPlaces){
       System.out.println(node.getLatitude()+","+node.getLongitude());
-    }*/
-    int[] array = g.fromLandmark(3430400);
-    /*try {
-      Utils.arrayToFile(array, "testOslo.txt");
-    } catch (Exception e) {
-      e.printStackTrace();
-    }*/
-    try {
-      int[] loadedArray = Utils.fileToArray("testOslo.txt", g.getSize());
-      System.out.println(loadedArray.length == g.getSize());
-    } catch (Exception e) {
-      e.printStackTrace();
     }
+
   }
 
 }
@@ -163,7 +154,6 @@ class Edge implements  Comparable<Edge>{
 }
 
 class Graph{
-  private final int size;
   private final HashMap<Integer, List<Edge>> adjacencyList = new HashMap<>();
   private final List<Node> nodes = new ArrayList<>();
 
@@ -172,14 +162,12 @@ class Graph{
   }
 
   public Graph(String inFile) throws IOException {
-    size = Utils.readFirstLine(inFile);
-    for(int i = 0; i < size; ++i) {
+    int numberOfNodes = Utils.readFirstLine(inFile);
+    for(int i = 0; i < numberOfNodes; ++i) {
       adjacencyList.put(i, new ArrayList<>());
     }
   }
 
-  public int getSize() {return size;}
-
   public void loadNodes(String inFile) {
     List<String> data = Utils.readFile(inFile);
     for(int i = 1; i < data.size(); ++i) {
@@ -198,6 +186,15 @@ class Graph{
     System.out.println("Edges loaded.");
   }
 
+  public void loadInverseEdges(String inFile){
+    List<String> data = Utils.readFile(inFile);
+    for(int i = 1; i < data.size(); ++i) {
+      String[] splitText = Utils.dividedText(data.get(i), 3);
+      addEdge(Integer.parseInt(splitText[1]), Integer.parseInt(splitText[0]), Integer.parseInt(splitText[2]));
+    }
+    System.out.println("Edges loaded.");
+  }
+
   public void readNodeInformation(String inFile){
     List<String> data = Utils.readFile(inFile);
     for(int i = 1; i < data.size(); ++i) {
@@ -210,6 +207,7 @@ class Graph{
   }
 
 
+
   public void addEdge(int start, int destination, int drivingTime) {
     adjacencyList.get(start).add(new Edge(start,destination, drivingTime));
   }
@@ -280,7 +278,6 @@ class Graph{
   public int [] fromLandmark(int landMark){
     PriorityQueue<Edge> priorityQueue = new PriorityQueue<>();
     int nodeSize = adjacencyList.size();
-    System.out.println(nodeSize);
     int[] pathWeight = new int[nodeSize];
     Arrays.fill(pathWeight, Integer.MAX_VALUE);
     pathWeight[landMark] = 0;
@@ -296,11 +293,11 @@ class Graph{
         for(Edge edge: adjacencyList.get(nextNode)){
           edge.setCurrentWeight(pathWeight[start]);
           priorityQueue.add(edge);
-        }
           index ++;
+        }
         priorityQueue.addAll(adjacencyList.get(nextNode));
       }
-      if(index == size) return pathWeight;
+      if(index == nodeSize) return pathWeight;
     }
     return null;
   }
@@ -342,25 +339,14 @@ class Utils{
     return currentDirectoryPath + System.getProperty("file.separator") +fileName;
   }
 
-  public static void arrayToFile(int[] array, String fileName) throws IOException{
-    FileWriter writer = new FileWriter(fileName);
-    for (int j : array) {
-      writer.write(j + "\n");
-    }
-    writer.close();
-  }
-
-  public static int[] fileToArray(String fileName, int size) throws Exception {
-    int[] array = new int[size];
-    try (BufferedReader reader = Files.newBufferedReader(Paths.get(fileName))) {
-      String currentLine = null;
-      int index = 0;
-      while((currentLine = reader.readLine()) != null) {
-        array[index] = Integer.parseInt(currentLine);
-        ++index;
-      }
+public void arrayToFile(int[] array, String fileName) throws IOException{
+    FileOutputStream out= new FileOutputStream(fileName);
+    FileChannel file = out.getChannel();
+    ByteBuffer but = file.map(FileChannel.MapMode.READ_WRITE,0, 4L * array.length);
+    for(int i : array){
+      but.putInt(i);
     }
-    return array;
+    file.close();
 }
 
   public static String[] dividedText(String line, int number){