Cod sursa(job #445811)

Utilizator idomiralinIdomir Alin idomiralin Data 24 aprilie 2010 13:13:33
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.95 kb
#include <stdlib.h>
#include <cstdio>
#include <vector>

using namespace std;

#define maxn 100010

vector<int>a[maxn];

int g[maxn],s[maxn],cost[maxn];
int n,m,st,l;

void bfs(int nod)
{
     int i,j;
     memset(cost, - 1, sizeof(cost));
     
     l = 1;
     cost[nod] = 0;
     s[l] = nod;
     
     for (i = 1; i <= l; i++)
         for (j = 0; j < g[s[i]]; j++)
         if (cost[a[s[i]][j]] == -1)
         {
            s[++l] = a[s[i]][j];
            cost[s[l]] = cost[s[i]] + 1;
            }

}
int main()
{
    int i,x,y;
    
    freopen("bfs.in","r",stdin);
    freopen("bfs.out","w",stdout);
    
    scanf("%d%d%d",&n,&m,&st);
    
    for (i = 1; i <= m; i++)
    {
        scanf("%d%d",&x,&y);
        a[x].push_back(y);
        }
    for (i = 1; i <= n; i++)
    g[i] = a[i].size();
    
    bfs(st);
    
    for (i = 1; i <= n; i++)
    printf("%d ",cost[i]);
    printf("\n");
return 0;
}