Cod sursa(job #2422453)

Utilizator IulianaRusuIuliana Rusu IulianaRusu Data 18 mai 2019 20:29:16
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.3 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>

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

int vizitat[100001];
vector <int> graph_bfs[100001];
int distanta[100001];
queue <int> coada;
int comp_conexe;

void BFS(int nod) {
    distanta[nod] = 0;
    vizitat[nod] = 1;
    coada.push(nod);
    //fout << "parcurgere bfs: ";
    while (coada.empty() == 0) {
        int x = coada.front();
       // fout << x << " ";
        coada.pop();
        int lim = graph_bfs[x].size();
        for (int i = 0; i < lim; i++) {
            int vecin = graph_bfs[x][i];
            if (vizitat[vecin] == 0) {
                coada.push(vecin);
                vizitat[vecin] = 1;
                    distanta[vecin] = distanta[x] + 1;
            }
        }
    }
}

int main() {
    int N, M, S;
    fin >> N >> M>>S;
    for (int i = 1; i <= M; i++) {
        int x, y;
        fin >> x>>y;
        graph_bfs[x].push_back(y);
    }
    for (int i = 1; i <= N; i++) {
        distanta[i] = -1;
    }
    
    BFS(S);

//    fout << "\nvectorul distantelor fata de start: ";
//    cout << "vector vizitat: ";
//    for (int i = 1; i <= nr_noduri; i++) {
//        cout << vizitat[i] << " ";
//    }
    for (int i = 1; i <= N; i++) {
        fout << distanta[i] << " ";
    }
    return 0;
}