Cod sursa(job #2517417)

Utilizator TocuAndreiTocu Andrei TocuAndrei Data 3 ianuarie 2020 15:47:51
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.08 kb
#include <iostream>
#include <vector>
#include <queue>
#include <fstream>
using namespace std;
ifstream fin("bfs.in");
ofstream fout("bfs.out");

int const maxim = 100005;
vector <int> arce[maxim];
queue <int> drum;
int distanta[maxim];
int n, m, s, lant = 0;

int BFS() {
    int nod, vecin;
    while(!drum.empty()) {
        nod = drum.front();
        drum.pop();
        for(unsigned int i = 0; i < arce[nod].size(); i++) {
            vecin = arce[nod][i];
            if(distanta[vecin] == -1) {
                drum.push(vecin);
                distanta[vecin] = distanta[nod] + 1;
            }
        }
    }
}

void citire() {
    fin >> n >> m >> s;
    for(int i = 1; i <= m; i ++) {
        int x, y;
        fin >> x >> y;
        arce[x].push_back(y);
    }
    for(int i = 1; i <= n; i ++) { // initializez toate pozitiile cu -1
        distanta[i] = -1;
    }
    distanta[s] = 0;
    drum.push(s);
    BFS();

    for(int i = 1; i <= n; i ++) {
        fout << distanta[i] << " ";
    }
}

int main() {
    citire();
    return 0;
}