Cod sursa(job #1424601)

Utilizator UAIC_HreapcaVlasNegrusUAIC Hreapca Vlas Negrus UAIC_HreapcaVlasNegrus Data 25 aprilie 2015 00:15:39
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.08 kb
#include <iostream>
#include <deque>
#include <vector>
#include <cstring>
#include <bitset>
#include <algorithm>
#define INF 1000010
#define ll long long
using namespace std;

int N, M, S, i , x, y, dist[100010];
vector<int> V[100010];
deque<int> Q;
bitset<100010> in_q;


int main()
{
    freopen("bfs.in","r",stdin);
    freopen("bfs.out","w",stdout);
    scanf("%d%d%d", &N, &M, &S);
    for(;M;--M)
    {
        scanf("%d%d", &x, &y);
        V[x].push_back(y);
    }
    for(i = 1; i <= N; i++)
        dist[i] = INF;
    in_q[S] = 1;
    Q.push_back(S);
    dist[S] = 0;
    while(!Q.empty())
    {
        x = Q.front();
        for(vector<int>::iterator it = V[x].begin(); it != V[x].end(); it++)
            if(dist[*it] > dist[x] + 1)
            {
                dist[*it] = dist[x] + 1;
                if(!in_q[*it])
                    Q.push_back(*it);
                in_q[*it] = 1;
            }
        in_q[x] = 0;
        Q.pop_front();
    }
    for(i=1;i<=N;i++)
    {
        x = -1;
        if(dist[i] != INF)
            x = dist[i];
        printf("%d ", x);
    }
    return 0;
}