Cod sursa(job #1740331)

Utilizator AplayLazar Laurentiu Aplay Data 11 august 2016 14:24:12
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.97 kb
#include <bits/stdc++.h>

#define NMAX 100001

#define pb push_back

using namespace std;

int N, M, S, dist[NMAX], x, y;
vector<int> graph[NMAX];
queue<int> q;

void bfs(int start) {
    int curr;

    for (int it = 1; it <= N; ++it) dist[it] = -1;
    dist[S] = 0;
    q.push(S);

    while (!q.empty()) {
        curr = q.front(); q.pop();
        for (vector<int>::iterator it = graph[curr].begin(); it < graph[curr].end(); ++it) {
            if (dist[*it] == -1) {
                dist[*it] = dist[curr] + 1;
                q.push(*it);
            }
        }
    }
}

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

    scanf("%d%d%d", &N, &M, &S);
    for (int it = 0; it < M; ++it) {
        scanf("%d%d", &x, &y);
        graph[x].pb(y);
    }

    bfs(S);
    for (int it = 1; it <= N; ++it) {
        printf("%d ", dist[it]);
    }

    fclose(stdin);
    fclose(stdout);
    return 0;
}