Dijkstra’s algorithm.

Question: Write a program to find shortest path from your home to college using Dijkstra’s algorithm.

Code:

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;

public class Dijkstras {

    static class vertex{
        int distance;
        boolean visited;
        int no;
        int previous;

        @Override        public String toString() {
            return "vertex{" +
                    "distance=" + distance +
                    ", visited=" + visited +
                    ", no=" + (no+1) +
                    ", previous=" + (previous+1) +
                    '}';
        }

        public vertex(int distance, boolean visited, int no, int previous) {
            this.distance = distance;
            this.visited = visited;
            this.no = no;
            this.previous = previous;
        }


    }

    public static void main(String[] nt){
        ArrayList<vertex> arrayList=new ArrayList<>();
        ArrayList<vertex> result=new ArrayList<>();
       /* int graph[][] = new int[][]{{0, 4, 0, 0, 0, 0, 0, 8, 0},                {4, 0, 8, 0, 0, 0, 0, 11, 0},                {0, 8, 0, 7, 0, 4, 0, 0, 2},                {0, 0, 7, 0, 9, 14, 0, 0, 0},                {0, 0, 0, 9, 0, 10, 0, 0, 0},                {0, 0, 4, 14, 10, 0, 2, 0, 0},                {0, 0, 0, 0, 0, 2, 0, 1, 6},                {8, 11, 0, 0, 0, 0, 1, 0, 7},                {0, 0, 2, 0, 0, 0, 6, 7, 0}        };       */       int[][] graph={{0,4,8,0,0},{0,0,5,8,10},{0,4,0,0,3},{0,0,0,0,6},{0,0,0,7,0}};
       for (int i=0;i<graph.length;i++){
            arrayList.add(new vertex(Integer.MAX_VALUE,false,i,Integer.MAX_VALUE));
        }

        arrayList.get(0).distance=0;
        arrayList.get(0).previous=0;

        Comparator<vertex> com=new Comparator<vertex>() {
            @Override            public int compare(vertex vertex, vertex t1) {
                return vertex.distance-t1.distance;
            }
        };

        vertex poped;
        while (arrayList.size()!=0){
            Collections.sort(arrayList,com);
            poped=arrayList.get(0);
            arrayList.remove(0);


            if(poped.visited==false){
                for (int i=0;i<graph[poped.no].length;i++){
                    if(graph[poped.no][i]!=0&& find(arrayList,i)!=Integer.MAX_VALUE){
                        int x=find(arrayList,i);
                            if(graph[poped.no][i]+poped.distance<arrayList.get(x).distance){
                                arrayList.get(x).distance=graph[poped.no][i]+poped.distance;
                                arrayList.get(x).previous=poped.no;
                            }
                    }
                }
                poped.visited=true;
                result.add(poped);
            }
        }

        Comparator<vertex>comp2=new Comparator<vertex>() {
            @Override            public int compare(vertex vertex, vertex t1) {
                return vertex.no-t1.no;
            }
        };
        Collections.sort(result,comp2);
        for(int i=0;i<result.size();i++){

            System.out.println(result.get(i).toString());
        }

    }

    static int find(ArrayList<vertex> arrayList,int n){
        int i=Integer.MAX_VALUE;

        for (int x=0;x<arrayList.size();x++){
            if(arrayList.get(x).no==n){
                return x;
            }
        }
        return i;
    }
}

Output: