Cod sursa(job #1979124)

Utilizator SenibelanMales Sebastian Senibelan Data 9 mai 2017 18:53:47
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.97 kb
#include <fstream>
#include <vector>
#include <queue>
#include <cstring>
using namespace std;

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

const int NMax = 100005;
vector <int> G[NMax];
int N,M,S;
int D[NMax];
queue <int> Q;
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()
{
    memset(D,-1,sizeof(D));
    D[S] = 0;
    Q.push(S);
    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)
        fout << D[i] << " ";
    fout << "\n";
}

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