Cod sursa(job #1487968)

Utilizator bpalaniciPalanici Bogdan bpalanici Data 17 septembrie 2015 18:29:24
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.96 kb
#include <bits/stdc++.h>

using namespace std;

vector <int> graf[100005];
int drum[100005];
int n, m, start;

void bfs(int start)
{
    bitset <100005> viz;
    deque <int> coada;
    coada.empty();
    viz.reset();
    coada.push_back(start);
    viz[start] = true;
    while (!coada.empty())
    {
        int nod = coada.front();
        coada.pop_front();
        for (const auto &it : graf[nod])
        if (!viz[it])
        {
            coada.push_back(it);
            viz[it] = true;
            drum[it] = drum[nod] + 1;
        }
    }
}

int main()
{
    freopen("bfs.in", "r", stdin);
    freopen("bfs.out", "w", stdout);
    scanf("%d %d %d", &n, &m, &start);
    for (int i = 1, a, b; i <= m; i++)
        scanf("%d %d", &a, &b),
        graf[a].push_back(b);
    bfs(start);
    for (int i = 1; i <= n; i++)
        if (i == start) printf("%d ", 0);
        else printf("%d ", drum[i] ? drum[i] : -1);
    return 0;
}