#include #include #include #include #include #include #include #include using namespace std; const int maxn = 1e5 + 10; int n, m; vector graph[maxn]; bool visited[maxn]; stack st; void topological_sort(int node) { visited[node] = true; cout << node + 1 << endl; for(int i = 0; i < (int) graph[node].size(); i++) { int neighbour = graph[node][i]; if(!visited[neighbour]) { topological_sort(neighbour); } } st.push(node); } int main() { cin >> n >> m; for(int i = 0; i < m; i++) { int a, b; cin >> a>> b; a--; b--; graph[a].push_back(b); } memset(visited, false, sizeof visited); for(int i = 0; i < n; i++) { if(!visited[i]) { topological_sort(i); } } while(!st.empty()) { cout << st.top() + 1 << " "; st.pop(); } return 0; }