Cod sursa(job #1583244)

Utilizator cordun_cristinaCristina Maria Cordun cordun_cristina Data 28 ianuarie 2016 20:01:54
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.93 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>

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

const int Nmax = 100005;

int n, m, x, D[Nmax];
vector <int> G[Nmax];
queue <int> Q;

void Read()
{
    f>>n>>m>>x;
    while(m--)
    {
        int x,y;
        f>>x>>y;
        G[x].push_back(y);
    }
}

void BFS()
{
    Q.push(x);
    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(D[Vecin] == -1)
            {
                D[Vecin] = D[Nod] + 1;
                Q.push(Vecin);
            }
        }
    }
}

void Print()
{
    for(int i = 1; i <= n; i++) g<<D[i]<<' ';
    g<<'\n';
}

int main()
{
    Read();
    for(int i = 1; i <= n; i++) D[i] = -1;
    D[x] = 0;
    BFS();
    Print();
    return 0;
}