Cod sursa(job #1365299)

Utilizator CosminRusuCosmin Rusu CosminRusu Data 28 februarie 2015 11:08:00
Problema Sortare topologica Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.29 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
#include <bitset>

using namespace std;

const int maxn = 50005;

int n, m, in[maxn];
vector <int> g[maxn], tsort;
queue <int> q;
bitset <maxn> used;

inline void dfs(int node) {
    used[node] = 1;
    for(vector <int> :: iterator it = g[node].begin() ; it != g[node].end() ; ++ it)
        if(!used[*it])
            dfs(*it);
    tsort.push_back(node);
}

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

    fin >> n >> m;
    for(int i = 1 ; i <= m ; ++ i) {
        int x, y;
        fin >> x >> y;
        g[x].push_back(y);
        ++ in[y];
    }
    for(int i = 1 ; i <= n ; ++ i)
        if(!used[i])
            dfs(i);
    for(vector <int> :: reverse_iterator it = tsort.rbegin() ; it != tsort.rend() ; ++ it)
        fout << *it << ' ';
    return 0;
    for(int i = 1 ; i <= n ; ++ i)
        if(!in[i])
            q.push(i);
    while(!q.empty()) {
        int node = q.front();
        tsort.push_back(node);
        q.pop();
        for(vector <int> :: iterator it = g[node].begin() ; it != g[node].end() ; ++ it)
            if(-- in[*it] == 0)
                q.push(*it);
    }
    for(vector <int> :: iterator it = tsort.begin() ; it != tsort.end() ; ++ it)
        fout << *it << ' ';
}