Prims

import java.util.*;
class prims{
    public static void main(String args[]){
        Scanner sc = new Scanner(System.in);
        System.out.println("Enter the size of Graph Matrix");
        int rows = sc.nextInt();
        int columns = sc.nextInt();
        int v = rows;
        int arr[][] = new int[rows][columns];
        for(int x = 0; x < rows; x++){
            for(int y = 0; y < columns; y++){
                arr[x][y] = sc.nextInt();
            }
        }
        int parent[] = new int[v];
        int key[] = new int[v];
        Boolean mst[] = new Boolean[v];
        for(int i = 0; i < v; i++){
            key[i] =Integer.MAX_VALUE;
            mst[i] = false;
        }
        key[0] = 0;
        parent[0] = -1;
        for(int count = 0; count < v - 1; count++){
            int u = minimum_key(key, mst, v);
            mst[u] = true;
            for(int i = 0; i < v; i++){
                if(arr[u][i] !=0 && mst[i] == false && arr[u][i] < key[i]){
                    parent[i] = u;
                    key[i] = arr[u][i];
                }
            }
        }

        System.out.println("Edge \tWeight");
        for (int i = 1; i < v; i++)
            System.out.println(parent[i] + " - " + i + "\t" + arr[i][parent[i]]);
    }
    public static int minimum_key(int key[], Boolean mst[], int v){
        int min = Integer.MAX_VALUE, min_index = -1;
        for(int i = 0; i < v; i++){
            if (mst[i] == false && key[i] < min) {
                min = key[i];
                min_index = i;
            }

        }
        return min_index;
    }

}