Cod sursa(job #1387791)

Utilizator cautionPopescu Teodor caution Data 14 martie 2015 17:57:14
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.91 kb
#include <fstream>
#include <vector>
#include <queue>
using namespace std;
int main()
{
    ifstream in("bfs.in");
    ofstream out("bfs.out");
    vector<long> *graf;
    queue<long> que;
    long *dist;
    long n, m, s, a, b, aux;
    in>>n>>m>>s;
    graf = new vector<long>[n+1];
    dist = new long[n+1];
    for(long i=1; i<=n; ++i)
        dist[i]=-1;
    for(long i=0; i<m; ++i)
    {
        in>>a>>b;
        graf[a].push_back(b);
    }
    que.push(s);
    dist[s]=0;
    while(!que.empty())
    {
        aux=que.front();
        que.pop();
        for(vector<long>::iterator it=graf[aux].begin(), ed=graf[aux].end(); it!=ed; ++it)
        {
            if(dist[*it]==-1)
            {
                dist[*it]=dist[aux]+1;
                que.push(*it);
            }
        }
    }
    for(long i=1; i<=n; ++i) out<<dist[i]<<' ';
    in.close(); out.close();
    return 0;
}