Cod sursa(job #2669551)

Utilizator Mihai145Oprea Mihai Adrian Mihai145 Data 7 noiembrie 2020 11:17:16
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.84 kb
#include <fstream>
#include <vector>
#include <queue>

using namespace std;

ifstream cin("bfs.in");
ofstream cout("bfs.out");

const int NMAX = 100000;
const int INF = 10 * NMAX;

int N, M, S;
vector <int> g[NMAX + 2];
int dist[NMAX + 2];

int main()
{
    cin >> N >> M >> S;

    for(int i = 1; i <= M; i++) {
        int x, y;
        cin >> x >> y;
        g[x].push_back(y);
    }

    for(int i = 1; i <= N; i++)
        dist[i] = INF;

    queue <int> q;
    q.push(S);
    dist[S] = 0;

    while(!q.empty()) {
        int node = q.front();
        q.pop();

        for(auto it : g[node])
            if(dist[it] == INF) {
                dist[it] = dist[node] + 1;
                q.push(it);
            }
    }

    for(int i = 1; i <= N; i++)
        if(dist[i] == INF) cout << -1 << ' ';
        else cout << dist[i] << ' ';

    return 0;
}