Cod sursa(job #1879592)

Utilizator cordun_cristinaCristina Maria Cordun cordun_cristina Data 15 februarie 2017 00:13:18
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.92 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>

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

int n, m, s, d[100005];
vector <int> G[100005];
bool Use[100005];
queue <int> Q;

void BFS()
{
    Q.push(s);
    Use[s] = 1;
    while(!Q.empty())
    {
        int nod = Q.front();
        Q.pop();
        for(int i = 0; i < (int)G[nod].size(); i++)
        {
            int vecin = G[nod][i];
            if(!Use[vecin])
            {
                Use[vecin] = 1;
                Q.push(vecin);
                d[vecin] = d[nod]+1;
            }
        }
    }
}

int main()
{
    f>>n>>m>>s;
    while(m--)
    {
        int x, y;
        f>>x>>y;
        G[x].push_back(y);
    }
    BFS();
    for(int i = 1; i <= n; i++)
    {
        if(d[i] == 0 && i != s) g<<-1<<' ';
        else g<<d[i]<<' ';
    }
    g<<'\n';
    return 0;
}