Cod sursa(job #1524231)

Utilizator vladbatalanBatalan Vlad vladbatalan Data 13 noiembrie 2015 18:25:45
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.78 kb
#include <fstream>
#include <vector>
#include <queue>

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

int n,m,s,marc[100001];
vector<int> v[100001];
queue<int> coada;

int main() {
    int x,y,a;
    f>>n>>m>>s;
    for(int i=1; i<=n; i++)
        marc[i]=-1;
    for(int i=1; i<=m; i++) {
        f>>x>>y;
        v[x].push_back(y);
    }
    marc[s]=0;
    coada.push(s);
    while(!coada.empty()) {
        a=coada.front();
        coada.pop();
        for(vector<int>::iterator it=v[a].begin();it!=v[a].end();it++){
            if(marc[*it]==-1){
                marc[*it]=marc[a]+1;
                coada.push(*it);
            }
        }
    }
    fout<<marc[1];
    for(int i=2;i<=n;i++)
        fout<<' '<<marc[i];
    return 0;
}