Cod sursa(job #1566804)

Utilizator tc_iuresiures tudor-cristian tc_iures Data 12 ianuarie 2016 17:20:34
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.03 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>

using namespace std;

const int Nmax = 100005;

vector<int> G[Nmax];
int D[Nmax], N, M, S;

void read()
{
    ifstream f("bfs.in");
    f >> N >> M >> S;
    for(int i = 0; i < M; i ++)
    {
        int x, y;
        f >> x >> y;
        G[x].push_back(y);
    }
    f.close();
}

void solve()
{
    for(int i = 1; i <= N; i ++)
    {
        D[i] = -1;
    }
    D[S] = 0;
    queue<int> Q;
    Q.push(S);
    while(!Q.empty())
    {
        int Node = Q.front();
        Q.pop();
        for(int i = 0; i < G[Node].size(); i ++)
        {
            int Ngh = G[Node][i];
            if(D[Ngh] == -1)
            {
                D[Ngh] = D[Node] + 1;
                Q.push(Ngh);
            }
        }
    }
}

void print()
{
    ofstream g("bfs.out");
    for(int i = 1; i <= N; i ++)
    {
        g << D[i] << " ";
    }
    g.close();
}

int main()
{
    read();
    solve();
    print();
    return 0;
}