Dijkstra’s Algorithm for Shortest Path Problem – GCC Program for Ubuntu

Dijkstra’s Algorithm finds the shortest path with the lower cost in a Graph. Dijkstra’s Algorithm solves the Single Source Shortest Path problem for a Graph. It is a Greedy algorithm and similar to Prim’s algorithm.

Read more about Dijkstra’s Algorithm for Shortest Path Problem.

Implementation

//**************************************************************************
// Implementation of Dijkstra’s Algorithm (Greedy Method to solve Shortest Path Problem)
//**************************************************************************

#include<stdio.h>

#define infinity 999

void dij(int n,int v,int cost[10][10],int dist[])
{
int i,u,count,w,flag[10],min;
for(i=1;i<=n;i++)
flag[i]=0,dist[i]=cost[v][i];
count=2;
while(count<=n)
{
min=99;
for(w=1;w<=n;w++)
if(dist[w]<min && !flag[w])
min=dist[w],u=w;
flag[u]=1;
count++;
for(w=1;w<=n;w++)
if((dist[u]+cost[u][w]<dist[w]) && !flag[w])
dist[w]=dist[u]+cost[u][w];
}
}

int main()
{
int n,v,i,j,cost[10][10],dist[10];

printf(“\n***** DIJKSTRA’S ALGORITHM FOR FINDING SHORTEST PATHS TO EACH NODE *****\n”);
printf(“\nEnter the Number of Nodes:”);
scanf(“%d”,&n);
printf(“\nEnter the Cost Matrix:\n”);
for(i=1;i<=n;i++)
for(j=1;j<=n;j++)
{
scanf(“%d”,&cost[i][j]);
if(cost[i][j]==0)
cost[i][j]=infinity;
}
printf(“\nEnter the Source Node:”);
scanf(“%d”,&v);
dij(n,v,cost,dist);
printf(“\n\n***** Shortest Paths to Each Node *****:\n”);
for(i=1;i<=n;i++)
if(i!=v)
printf(“Node %d -> Node %d, cost=%d\n\n”,v,i,dist[i]);
return 0;
}

Tagged: Dijkstra’s Algorithm, Shortest Path problem, Shortest Paths