5. Write a program to simulate the behaviour of link state routing protocol to find suitable path for transmission.

Download The write up here

Dijkstra.java

import java.util.*;

public class Dijkstra
{
  public  int distance[] = new int[10];
  public  int cost[][] = new int[10][10];

  public void calc(int n,int s)
  {
  int flag[] = new int[n+1];
  int i,minpos=1,k,c,minimum;
      for(i=1;i<=n;i++)
  {
            flag[i]=0;
      this.distance[i]=this.cost[s][i];
    }
      c=2;
  while(c<=n)
  {
    minimum=99;
    for(k=1;k<=n;k++)
    {
          if(this.distance[k]<minimum && flag[k]!=1)
        {
        minimum=this.distance[i];
        minpos=k;
        }
      }
            flag[minpos]=1;
      c++;
      for(k=1;k<=n;k++)
  {
          if(this.distance[minpos]+this.cost[minpos][k] <  this.distance[k] && flag[k]!=1 )
    this.distance[k]=this.distance[minpos]+this.cost[minpos][k];
  } 
  }
 
  }
  public static void main(String args[])
  {
  int nodes,source,i,j;
  Scanner in = new Scanner(System.in);
  System.out.println("Enter the Number of Nodes \n");
  nodes = in.nextInt();
  Dijkstra d = new Dijkstra();
  System.out.println("Enter the Cost Matrix Weights: \n");
        for(i=1;i<=nodes;i++)
          for(j=1;j<=nodes;j++)
    {
            d.cost[i][j]=in.nextInt();
            if(d.cost[i][j]==0)
              d.cost[i][j]=999;
          }
  System.out.println("Enter the Source Vertex :\n");
  source=in.nextInt();
 
      d.calc(nodes,source);
  System.out.println("The Shortest Path from Source \t"+source+"\t to all other vertices are : \n");
        for(i=1;i<=nodes;i++)
          if(i!=source)
  System.out.println("source :"+source+"\t destination :"+i+"\t MinCost is :"+d.distance[i]+"\t");
       
 
}
}

/*OUTPUT

iotlab@iotlab-Veriton-M200-B360:~$ javac Dijkstra.java 

iotlab@iotlab-Veriton-M200-B360:~$ java Dijkstra 

Enter the Number of Nodes 

5

Enter the Cost Matrix Weights: 

0 1 0 2 0

1 0 1 0 4

0 1 0 0 3

2 0 0 0 3

0 4 3 3 0

Enter the Source Vertex :

1

The Shortest Path from Source 1 to all other vertices are : 

source :1 destination :2 MinCost is :1

source :1 destination :3 MinCost is :2

source :1 destination :4 MinCost is :2

source :1 destination :5 MinCost is :5

*/