Cod sursa(job #2035210)

Utilizator zeboftwAlex Mocanu zeboftw Data 9 octombrie 2017 08:17:44
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.19 kb
#include <fstream>
#include <queue>
#include <set>
#include <vector>
#include <cstring>
#include <iostream>

using namespace std;

ifstream fin ("bfs.in");
ofstream fout("bfs.out");

const int N_MAX = 100005;
const int INF = 0x3f3f3f3f;

vector<int> AD[N_MAX];
int dist[N_MAX];

int main()
{
    int n, m, s;

    fin >> n >> m >> s;

    for (int i=1; i <= m; i++)
    {
        int from, to;
        fin >> from >> to;
        if (from != to)
            AD[from].push_back(to);
    }

    queue<int> coada;
    memset(dist, INF, sizeof(dist));
    dist[s]= 0;

    coada.push(s);

    while (!coada.empty())
    {
        int current = coada.front();
        coada.pop();
        {
            for (vector<int>::iterator it = AD[current].begin(); it != AD[current].end(); it++)
            {
                int node = *it;
                if (dist[node] == INF)
                {
                    coada.push(node);
                    dist[node] = dist[current] + 1;
                }
            }

        }
    }

    for (int i=1; i <= n; i++)
    {
        if (dist[i] == INF) dist[i]=-1;
        fout << dist[i] << ' ';
    }
    return 0;
}