Cod sursa(job #2044192)

Utilizator SederfoMarius Vlad Sederfo Data 20 octombrie 2017 23:59:23
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.95 kb
#include <iostream>
#include <fstream>
#include <queue>
#include <vector>

using namespace std;

ifstream fin ("bfs.in");
ofstream fout ("bfs.out");  //BSF.IN .OUT

int N, M, S, D[100001];
vector <int> G[100001];
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()
{
    Q.push(S);
    for (int i=1; i<=N; i++)
        D[i]=-1;
    D[S]=0;
    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] << " ";
}

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