Cod sursa(job #1992753)

Utilizator zanugMatyas Gergely zanug Data 21 iunie 2017 12:41:13
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.97 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
#include <cstdio>

#define ll long long
#define pb push_back

using namespace std;

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

const int N = 1e5 + 10;
const int M = 1e6 + 10;

int n, m, s;
vector < int > v[N];
int a[N];
queue < int > q;

int main()
{
    fin >> n >> m >> s;

    int x, y;
    for(int i = 0; i < m; ++i)
    {
        fin >> x >> y;
        v[x].pb(y);
    }

    for(int i = 1; i <= n; ++i)
        a[i] = -1;
    a[s] = 0;

    q.push(s);

    while(q.size())
    {
        int cnod = q.front();

        for(int i = 0; i < v[cnod].size(); ++i)
        {
            int nnod = v[cnod][i];

            if(a[nnod] == -1)
            {
                a[nnod] = a[cnod]+1;
                q.push(nnod);
            }
        }
        q.pop();
    }

    for(int i = 1; i <= n; ++i)
        fout << a[i] << " ";

    return 0;
}