Cod sursa(job #3302533)

Utilizator vladm98Munteanu Vlad vladm98 Data 8 iulie 2025 15:53:38
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.97 kb
#include <bits/stdc++.h>

using namespace std;

vector <int> graph[100005];
int distances[100005];

void bfs(int source, int n) {
    for (int i = 1; i <= n; ++i) {
        distances[i] = n + 1; // INF
    }
    queue<int> q;
    q.push(source);
    distances[source] = 0;

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

        for (auto vecin : graph[node]) {
            if (distances[vecin] > distances[node] + 1) {
                distances[vecin] = distances[node] + 1;
                q.push(vecin);
            }
        }
    }

    for (int i = 1; i <= n; ++i) {
        if (distances[i] == n + 1) {
            distances[i] = -1;
        }
        cout << distances[i] << " ";
    }
}

int main()
{
    freopen("bfs.in", "r", stdin);
    freopen("bfs.out", "w", stdout);
    int n, m, s;
    cin >> n >> m >> s;
    for (int i = 1; i <= m; ++i) {
        int x, y;
        cin >> x >> y;
        graph[x].push_back(y);
    }

    bfs(s, n);
    return 0;
}