Cod sursa(job #1435901)

Utilizator CiobraNume Prenume Ciobra Data 14 mai 2015 19:03:31
Problema BFS - Parcurgere in latime Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 1.01 kb
#include <iostream>
#include <fstream>
#include <queue>
#include <vector>
#include <cstdio>
#include <cstring>

using namespace std;

#define MAX 100005

vector<int> v[MAX];
int cost[MAX];

void init(int n) {
    for (int i = 0; i <= n; ++i) {
        cost[i] = -1;
    }
}


void bfs(int n) {
    queue <int> q;
    q.push(n);
    cost[n] = 0;
    while (!q.empty()) {
        n = q.front();
        q.pop();
        for (int i = 0; i < v[n].size(); ++i) {
            if (cost[v[n][i]] == -1) {
                q.push(v[n][i]);
                cost[v[n][i]] = cost[n]+1;
            }
        }

    }

}

int main()
{
    ifstream f("bfs.in");
    ofstream g("bfs.out");

    int n, m, x, y, s;
    f >> n >> m >> s;

    for (int i = 1; i <= m; i++) {
        f >> x >> y;
        //cerr<<x<<' '<<y;
        v[x].push_back(y);
    }

    init(n);
    bfs(s);
    for (int i = 1; i <= n;i++)
        cout << cost[i] << " ";

    f.close();
    g.close();
    return 0;
}