Cod sursa(job #1311993)

Utilizator emanuel_rRamneantu Emanuel emanuel_r Data 8 ianuarie 2015 19:51:25
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.03 kb
#include <fstream>
#include <vector>
#include <queue>
#define NMax 100005

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

int N,M,S;
vector <int> G[NMax];
queue <int> Q;
int D[NMax];

void Read()
{
    fin>>N>>M>>S;
    for(int i=1;i<=M;i++)
        {
            int x,y;
            fin>>x>>y;
            G[x].push_back(y);
        }
}

void BFS()
{
    for(int i=1;i<=N;i++)
        D[i] = -1;

    Q.push(S);
    D[S] = 0;

    while(!Q.empty())
        {
            int Nod = Q.front(); Q.pop();
            for(unsigned int i = 0; i<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++)
        fout<<D[i]<<" ";
}

int main()
{
    Read();
    BFS();
    Print();
    return 0;
}