Cod sursa(job #2166431)

Utilizator alex.surdubobAlex Surdu alex.surdubob Data 13 martie 2018 17:04:50
Problema BFS - Parcurgere in latime Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 0.93 kb
#include <fstream>
#include <vector>
#include <queue>
using namespace std;

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

vector<int> vecini[100010];
queue<int> q;

int d[100010];
bool viz[100010];

int main()
{
    int n, m, s;
    fin >> n >> m >> s;
    for(int i = 0 ; i < m ; i++)
    {
        int a, b;
        fin >> a >> b;
        vecini[a].push_back(b);
    }

    q.push(s);
    viz[s] = 1;
    while(!q.empty())
    {
        int t = q.front();
        q.pop();
        for(int i = 0 ; i < vecini[t].size(); i++)
        {
            if(!viz[vecini[t][i]])
            {
                viz[vecini[t][i]] = 1;
                d[vecini[t][i]] = d[t] + 1;
                q.push(vecini[t][i]);
            }
        }
    }
    for(int i = 1; i <= n; i++)
    {
        if(d[i] == 0 && i != s)
        {
            fout << -1 << ' ';
        }
        else
        {
            fout << d[i] << ' ';
        }

    }

    return 0;
}