#include using namespace std; const long long INF = 1000000; struct monoid{ bool e; long long aa, ab, ba, bb; monoid(){ e = true; } monoid(int x){ e = false; if (x == 1){ aa = 1, ab = -INF, ba = -INF, bb = -INF; } else { aa = -INF, ab = -INF, ba = -INF, bb = 1; } } }; monoid f(monoid L, monoid R){ if (L.e){ return R; } if (R.e){ return L; } monoid ans; ans.e = false; ans.aa = max({L.aa, R.aa, L.aa + R.ba, L.ab + R.aa}); ans.ab = max({L.ab, R.ab, L.aa + R.bb, L.ab + R.ab}); ans.ba = max({L.ba, R.ba, L.ba + R.ba, L.bb + R.aa}); ans.bb = max({L.bb, R.bb, L.ba + R.bb, L.bb + R.ab}); return ans; } struct segment_tree{ int N; vector ST; segment_tree(int N2){ N = 1; while (N < N2){ N *= 2; } ST = vector(N * 2 - 1); } void update(int i, int x){ i += N - 1; ST[i] = monoid(x); while (i > 0){ i = (i - 1) / 2; ST[i] = f(ST[i * 2 + 1], ST[i * 2 + 2]); } } monoid all(){ return ST[0]; } monoid range_fold(int L, int R, int i, int l, int r){ if (r <= L || R <= l){ return monoid(); } else if (L <= l && r <= R){ return ST[i]; } else { int m = (l + r) / 2; return f(range_fold(L, R, i * 2 + 1, l, m), range_fold(L, R, i * 2 + 2, m, r)); } } monoid range_fold(int L, int R){ return range_fold(L, R, 0, 0, N); } }; int main(){ int T; cin >> T; for (int i = 0; i < T; i++){ int N; cin >> N; vector P(N); for (int j = 0; j < N; j++){ cin >> P[j]; P[j]--; } vector Q(N); for (int j = 0; j < N; j++){ Q[P[j]] = j; } long long ans = 0; segment_tree ST(N); for (int j = 0; j < N; j++){ ST.update(j, -1); } for (int j = 0; j <= N; j++){ monoid tmp = ST.all(); ans = max(ans, max({tmp.aa, tmp.ab, tmp.ba, tmp.bb})); if (j < N){ ST.update(Q[j], 1); } } cout << ans << endl; } }