Cod sursa(job #2717669)

Utilizator AlexZeuVasile Alexandru AlexZeu Data 7 martie 2021 19:58:05
Problema BFS - Parcurgere in latime Scor 10
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.14 kb
#include <bits/stdc++.h>
using namespace std;

int noduri, arce, S, dist[100100], fr[100100];
vector<int> vecini[100100];

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

void BFS(int x, int parcurgeri) {
    if (fr[x] == 1) {
        return;
    }
    fr[x] = 1;
    dist[x] = min(dist[x], parcurgeri);
    if (x != S) {
        for (int i = 0; i < vecini[x].size(); ++i) {
            BFS(vecini[x][i], parcurgeri + 1);
        }
    }
}

int main() {
    fin.tie(0);
    ios::sync_with_stdio(0);
    fin >> noduri >> arce >> S;
    for (int i = 1; i <= arce; ++i) {
        int x, y;
        fin >> x >> y;
        vecini[x].push_back(y);
    }
    for (int i = 1; i <= noduri; ++i) {
        dist[i] = INT_MAX;
    }
    for (int i = 0; i < vecini[S].size(); ++i) {
        if (vecini[S][i] == S) {
            fr[vecini[S][i]] = 1;
            dist[vecini[S][i]] = 0;
        }
        BFS(vecini[S][i], 1);
    }
    for (int i = 1; i <= noduri; ++i) {
        if (dist[i] == INT_MAX) {
            fout << "-1 ";
        }
        else {
            fout << dist[i] << " ";
        }
    }
    return 0;
}