Cod sursa(job #2315492)

Utilizator IulianOleniucIulian Oleniuc IulianOleniuc Data 10 ianuarie 2019 00:00:10
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.89 kb
#include <queue>
#include <vector>
#include <fstream>

#define NMAX 100010

using std::queue;
using std::vector;

std::ifstream fin("bfs.in");
std::ofstream fout("bfs.out");

int n, m, s;
int dp[NMAX];
vector<int> ad[NMAX];

void bfs(int src) {
    queue<int> q;
    for (int i = 1; i <= n; i++)
        dp[i] = -1;

    dp[src] = 0;
    q.push(src);

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

        for (int nghb : ad[node])
            if (dp[nghb] == -1) {
                dp[nghb] = dp[node] + 1;
                q.push(nghb);
            }
    }
}

int main() {
    int x, y;

    fin >> n >> m >> s;
    for (int i = 0; i < m; i++) {
        fin >> x >> y;
        ad[x].push_back(y);
    }

    bfs(s);
    for (int i = 1; i <= n; i++)
        fout << dp[i] << ' ';
    fout << '\n';

    fout.close();
    return 0;
}