Cod sursa(job #2725521)

Utilizator filicriFilip Crisan filicri Data 19 martie 2021 09:23:31
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.82 kb
#include <fstream>
#include <vector>
#include <queue>
using namespace std;

int main() {
    ifstream f("bfs.in");
    ofstream g("bfs.out");
    int n, m, s, x, y;
    f >> n >> m >> s;
    vector<int> G[n + 1];
    int dist[n + 1];
    for (int i = 1; i <= n; i++)
        dist[i] = 0;
    for (int i = 0; i < m; i++) {
        f >> x >> y;
        G[x].push_back(y);
    }
    queue<int> q;
    q.push(s);
    while (!q.empty()) {
        int node = q.front();
        q.pop();
        for (int ne: G[node])
            if (dist[ne] == 0 && ne != s) {
                dist[ne] = dist[node] + 1;
                q.push(ne);
            }
    }
    for (int i = 1; i <= n; i++)
        if (dist[i] == 0 && i != s)
            g << -1 << ' ';
        else
            g << dist[i] << ' ';
    f.close();
    g.close();
    return 0;
}