Cod sursa(job #1198292)

Utilizator armandpredaPreda Armand armandpreda Data 15 iunie 2014 12:45:28
Problema BFS - Parcurgere in latime Scor 70
Compilator cpp Status done
Runda Arhiva educationala Marime 0.86 kb
#include <cstdio>
#include <vector>
#include <queue>
using namespace std;
#define MAX 100000
vector <int> lista[MAX];
queue <int> q;
int n, m, s, v[MAX];
void bfs(int sursa);
int main()
{
    int i, x, y;
    freopen("bfs.in", "r", stdin);
    freopen("bfs.out", "w", stdout);
    scanf("%d%d%d", &n, &m, &s);
    for(i=1; i<=m; i++){
        scanf("%d%d", &x, &y);
        lista[x].push_back(y);
    }
    bfs(s);
    for(i=1; i<=n; i++)
        if(v[i]==0) printf("-1 ");
        else printf("%d ", v[i]-1);
}
void bfs(int sursa){
    int i;
    q.push(sursa);
    v[sursa] = 1;
    while(!q.empty()){
        int nod = q.front();
        q.pop();
        for(i=0; i<lista[nod].size(); i++)
            if(v[lista[nod][i]]==0){
                v[lista[nod][i]] = 1 + v[nod];
                q.push(lista[nod][i]);
            }
    }
}