#include <bits/stdc++.h>

using namespace std;

void dfs_visit(vector<vector<int>>& Graph, int src, stack<int>& s, vector<bool>& visit) {

visit[src] = 1;

for(int i = 0; i < Graph[src].size(); i++)

if(visit[Graph[src][i]] == 0)

dfs_visit(Graph, Graph[src][i], s, visit);

s.push(src);

}

void dfs(vector<vector<int>>& Graph, int v, stack<int>& s) {

vector<bool> visit(v);

for(int i = 0; i < v; i++)

if(visit[i] == 0)

dfs_visit(Graph, i, s, visit);

}

void topological_sort(vector<vector<int>>& Graph, int v) {

stack<int> s;

dfs(Graph, v, s);

while(!s.empty()) {

cout << s.top() << ' ';

s.pop();

}

cout << '\n';

}

int main() {

int v, e, a, b;

// all vertices are labelled from 0 to v-1

cin >> v >> e;

vector<vector<int>> Graph(v);

// all directed edges

for(int i = 0; i < e; i++) {

cin >> a >> b;

// edge a -> b

Graph[a].push_back(b);

}

topological_sort(Graph, v);

return 0;

}