Cod sursa(job #1380178)

Utilizator Corina1997Todoran Ana-Corina Corina1997 Data 6 martie 2015 22:44:48
Problema Sortare topologica Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.94 kb
#include <fstream>
#include <vector>
#include <queue>
using namespace std;

ifstream is("sortaret.in");
ofstream os("sortaret.out");

vector<vector<int>>  g;
vector<bool> v;
vector<int> gr;
queue<int> Q;

int n, m, x, y;

int main()
{
    is >> n >> m;
    g.resize(n+1);
    gr.resize(n+1);
    v.resize(n+1);
    for  ( int i = 1; i <= m; i++ )
    {
        is >> x >> y;
        g[x].push_back(y);
        gr[y]++;
    }
    for ( int i = 1; i <= n; i++ )
        if ( gr[i] == 0 )
        {
            Q.push(i);
            v[i] = true;
        }
    int k;
    while( !Q.empty() )
    {
        k = Q.front();
        Q.pop();
        os << k << ' ';
         for ( const auto& f : g[k] )
            if ( !v[f] )
            {
                gr[f]--;
                if ( gr[f] == 0 )
                    Q.push(f), v[f] = true;
            }
    }
    is.close();
    os.close();
    return 0;
}