Dijkstra_Algo.c

#include<stdio.h>
#define infinity 999
void dij(int n, int v,int cost[20][20], int dist[])
{
int i,u,count,w,flag[20], 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[20][20],dist[20];

printf("enter the number of nodes:");
scanf("%d",&n);

printf("\n enter 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("\n enter the source vertex:");
scanf("%d",&v);

dij(n,v,cost,dist);

printf("\n shortest path : \n");

for(i=1;i<=n;i++)

if(i!=v)
printf("%d->%d,cost=%d\n",v,i,dist[i]);
}