#include <fstream>
#include <list>
#include <map>

void dfs(int node, std::map<int, std::list<int>>& adj, std::list<int>& sorted, std::map<int, bool>& visited)
{
    visited[node] = true;
    for (auto& neighbour : adj[node])
        if (!visited[neighbour])
            dfs(neighbour, adj, sorted, visited);
    sorted.push_back(node);
}

int main()
{
    std::ifstream in("sortaret.in");
    int n, m; in >> n >> m;

    std::map<int, std::list<int>> adj;
    for (int i = 0; i < m; i++)
    {
        int x, y; in >> x >> y;
        adj[x].push_back(y);
    }

    in.close();

    //topological sort
    std::list<int> sorted;
    std::map<int, bool> visited;

    for(int i = 0; i < n; i++)
        if(!visited[i])
            dfs(i, adj, sorted, visited);
    sorted.reverse();

    std::ofstream out("sortaret.out");
    for (auto& node : sorted)
        out << node << ' ';
    out.close();
    return 0;
}