Cod sursa(job #2984685)

Utilizator GabiTulbaGabi Tulba-Lecu GabiTulba Data 24 februarie 2023 17:31:58
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.98 kb
#include <cstdio>
#include <queue>
#include <vector>

using namespace std;

const int MAX_N = 100000;
const int INF = 1e9; // 1 * 10^9 = 1.000.000.000

int n, m, start;
vector<int> dist;
vector<int> G[MAX_N + 1];

void BFS(int node) {
    queue<int> q;
    q.push(node);
    dist[node] = 0;

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

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

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

    scanf("%d%d%d", &n, &m, &start);

    dist.resize(n + 1, INF);

    for (int i = 1; i <= m; i++) {
        int x, y;

        scanf("%d%d", &x, &y);

        G[x].push_back(y);
    }

    BFS(start);

    for (int i = 1; i <= n; i++) {
        if (dist[i] == INF) {
            printf("-1 ");
        } else {
            printf("%d ", dist[i]);
        }
    }

    return 0;
}