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//#include <gtest/gtest.h>
#include <iostream>
#include <vector>
#include <algorithm>
#include <iostream>
#include <algorithm>
#include <vector>
#include <numeric>
using std::vector;
using std::pair;
using namespace std;
// https://stackoverflow.com/questions/1577475/c-sorting-and-keeping-track-of-indexes
template <typename T>
vector<size_t> sort_indexes(const vector<T>& v) {
// initialize original index locations
vector<size_t> idx(v.size());
iota(idx.begin(), idx.end(), 0);
// sort indexes based on comparing values in v
// using std::stable_sort instead of std::sort
// to avoid unnecessary index re-orderings
// when v contains elements of equal values
stable_sort(idx.begin(), idx.end(),
[&v](size_t i1, size_t i2) {return v[i1] > v[i2]; });
return idx;
}
void postVisit(int v, vector<int>& clock, vector<int>& postV) {
postV[v] = clock[0];
clock[0] = clock[0] + 1;
}
void explore(int v, vector<vector<int>> &adj, vector<bool>& visited, vector<int>& postV, vector<int>& clock) {
visited[v] = true;
for (int w : adj[v]) {
if (!visited[w])
explore(w, adj, visited, postV, clock);
}
postVisit(v, clock, postV);
}
void dfs(vector<vector<int> >& adj, vector<bool>& visited, vector<int>& postV, vector<int>& clock) {
for (size_t v = 0; v < adj.size(); v++) {
if (!visited[v])
explore(v, adj, visited, postV, clock);
}
}
vector<int> toposort(vector<vector<int> > adj) {
vector<bool> visited(adj.size(), false);
vector<int> order;
vector<int> postV(adj.size(), 0);
vector<int> clock(1, 0);
dfs(adj, visited, postV, clock);
for (auto i : sort_indexes(postV)) {
order.push_back(i);
}
return order;
}
int main() {
size_t n, m;
std::cin >> n >> m;
vector<vector<int> > adj(n, vector<int>());
for (size_t i = 0; i < m; i++) {
int x, y;
std::cin >> x >> y;
adj[x - 1].push_back(y - 1);
}
vector<int> order = toposort(adj);
for (size_t i = 0; i < order.size(); i++) {
std::cout << order[i] + 1 << " ";
}
}
//TEST(Acyclicity, ac1) {
// vector<vector<int>> adj = { { 1 }, { 2 }, { 0 }, { 0 } };
// ASSERT_EQ(acyclic(adj), 1);
//}
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