Cod sursa(job #1540397)

Utilizator PaulStighiStiegelbauer Paul-Alexandru PaulStighi Data 2 decembrie 2015 19:02:21
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.07 kb
#include <fstream>
#include <vector>
#include <cstring>
#include <queue>
using namespace std;

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

const int NMax = 100000;

int N,M,S;
vector <int> G[NMax + 5];
int D[NMax + 5];
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;
}