Cod sursa(job #1850700)

Utilizator GinguIonutGinguIonut GinguIonut Data 18 ianuarie 2017 20:39:46
Problema Sortare topologica Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 1.01 kb
#include <fstream>
#include <vector>
#include <queue>

#define nMax 50001
#define pb push_back

using namespace std;

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

int n, m, S, nrSol;
int gradIn[nMax], viz[nMax], Sol[nMax];
vector<int> G[nMax];
queue<int> Q;

void solve()
{
    for(int i=1; i<=n; i++)
        if(gradIn[i]==0)
            S=i;

    for(Q.push(S), viz[S]=1; !Q.empty(); Q.pop())
    {
        int node=Q.front();
        Sol[++nrSol]=node;
        for(vector<int>::iterator it=G[node].begin(); it!=G[node].end(); it++)
        {
            int fiu=*it;
            gradIn[fiu]--;
            if(gradIn[fiu]==0 && viz[fiu]==0)
            {
                viz[fiu]=1;
                Q.push(fiu);
            }
        }
    }

    for(int i=1; i<=nrSol; i++)
        fout<<Sol[i]<<" ";
}

int main()
{
    int a, b;
    fin>>n>>m;

    for(int i=1; i<=m; i++)
    {
        fin>>a>>b;
        G[a].pb(b);
        gradIn[b]++;
    }

    solve();
}