Cod sursa(job #1344388)

Utilizator tudorv96Tudor Varan tudorv96 Data 16 februarie 2015 18:06:15
Problema Sortare topologica Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.74 kb
#include <fstream>
#include <vector>
#include <queue>
using namespace std;

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

const int N = 50005;

int n, m;
queue <int> Q;
vector <int> g[N], gint(N, 0);

int main() {
    fin >> n >> m;
    while (m--) {
        int x, y;
        fin >> x >> y;
        gint[y]++;
        g[x].push_back(y);
    }
    for (int i = 1; i <= n; ++i)
        if (!gint[i])
            Q.push(i);
    while (Q.size()) {
        int x = Q.front();
        Q.pop();
        fout << x << " ";
        for (vector <int> :: iterator it = g[x].begin(); it != g[x].end(); ++it) {
            gint[*it]--;
            if (!gint[*it])
                Q.push(*it);
        }
    }
}