Cod sursa(job #3245213)

Utilizator TeddyDinutaDinuta Eduard Stefan TeddyDinuta Data 27 septembrie 2024 22:07:49
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.85 kb
#include <bits/stdc++.h>

using namespace std;
ifstream in("bfs.in");
ofstream out("bfs.out");

int n, m, s;
int x, y;

void bfs(int start, vector<int>& dp, vector<vector<int>> &adj) {
    dp[start] = 0;
    queue<int> q;

    q.push(start);

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

        for (auto it : adj[node]) {
            if (dp[it] == 1e9) {
                dp[it] = dp[node] + 1;
                q.push(it);
            }
        }
    }
}

int main() {
    in >> n >> m >> s;
    vector<vector<int>> adj(n + 1, vector<int>());

    for (int i = 1; i <= m; i++) {
        in >> x >> y;
        adj[x].push_back(y);
    }

    vector<int> dp(n + 1, 1e9);
    bfs(s, dp, adj);

    for (int i = 1; i <= n; i++) {
        if (dp[i] == 1e9) {
            dp[i] = -1;
        }

        out << dp[i] << ' ';
    }
    return 0;
}