Cod sursa(job #1974365)

Utilizator gabrielinelusGabriel-Robert Inelus gabrielinelus Data 27 aprilie 2017 13:59:54
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.82 kb
#include <bits/stdc++.h>

using namespace std;
vector<vector<int> > G;
vector<int> dist;

int N, M, S;



void BFS(int k)
{
    queue<int> Q;
    Q.push(k);
    fill(dist.begin(), dist.end(), -1);
    dist[k] = 0;
    while(!Q.empty()) {
      k = Q.front(); Q.pop();
      for(auto it : G[k])
        if(dist[it] == -1) {
            dist[it] = dist[k] + 1;
            Q.push(it);
        }
    }

}

int main()
{
    freopen("bfs.in", "r", stdin);
    freopen("bfs.out", "w", stdout);

    scanf("%d%d%d",&N, &M, &S);
    dist.resize(N + 1);
    G.resize(N + 1);

    for(int i = 1; i <= M; ++i) {
        int a,b;
        scanf("%d%d", &a, &b);
        G[a].push_back(b);
    }

    BFS(S);
    for(int i = 1; i <= N; ++i)
        printf("%d ", dist[i]);
    printf("\n");

    return 0;
}