#include using namespace std; const int N = 1e5 + 5, M = N << 1; int n, m, ans[N], al; int in[N]; // 链式前向星 int e[M], h[N], idx, w[M], ne[M]; void add(int a, int b, int c = 0) { e[idx] = b, ne[idx] = h[a], w[idx] = c, h[a] = idx++; } void topsort() { priority_queue q; for (int i = 1; i <= n; i++) if (in[i] == 0) q.push(i); while (q.size()) { int u = q.top(); q.pop(); ans[al++] = u; for (int i = h[u]; ~i; i = ne[i]) { int j = e[i]; in[j]--; if (in[j] == 0) q.push(j); } } } void solve() { cin >> n >> m; al = 0, idx = 0; memset(h, -1, sizeof h); while (m--) { int u, v; cin >> u >> v; add(v, u); in[u]++; } topsort(); for (int i = al - 1; i >= 0; i--) { cout << ans[i]; if (i != 0) cout << ' '; else cout << endl; } } int main() { ios::sync_with_stdio(false), cin.tie(0); int T; cin >> T; while (T--) solve(); return 0; }