Prims Algorithm

#include<stdio.h>
#include<time.h>
int a,b,u,v,n,i,j,ne=1,st,et;
int visited[10]={0},min,mincost=0,cost[10][10];
void main()
{
 printf("Enter the number of nodes:");
 scanf("%d",&n);
 printf("Enter the adjacency matrix: ");
 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]=999;
  }
  st=clock();
 visited[1]=1;
 printf("n");
 while(ne<n)
 {
  for(i=1,min=999;i<=n;i++)
   for(j=1;j<=n;j++)
    if(cost[i][j]<min)
     if(visited[i]!=0)
     {
      min=cost[i][j];
      a=u=i;
      b=v=j;
     }
  if(visited[u]==0 || visited[v]==0)
  {
   printf("Edge %d:(%d %d) cost:%d",ne++,a,b,min);
   mincost+=min;
   visited[b]=1;
  }
  cost[a][b]=cost[b][a]=999;
 }
 printf("Minimun cost=%d",mincost);
 et=clock();
   printf("Start Time =%d\nEnd Time =%d",st,et);
}