#include // {{{ // https://codeforces.com/blog/entry/96344 #pragma GCC optimize("O2,unroll-loops") #pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt") using namespace std; using i32 = int32_t; using u32 = uint32_t; using i64 = int64_t; using u64 = uint64_t; using f64 = double; using f128 = long double; // }}} void solve() { u32 n; cin >> n; vector a(n); for (u32 i = 0; i < n; ++i) { cin >> a[i]; } vector prefix_one(n + 1, 0), postfix_zero(n + 2, 0); for (u32 i = 0; i < n; ++i) { prefix_one[i + 1] = (a[i] == 1) + prefix_one[i]; } for (i32 i = n - 1; i >= 0; --i) { postfix_zero[i + 1] = postfix_zero[i + 2] + (a[i] == 0); } postfix_zero[0] = postfix_zero[1]; i64 ans = 0; for (u32 i = 0; i < n; ++i) { if (a[i] == 1) ans += postfix_zero[i + 2]; } i64 init = ans; for (u32 i = 0; i < n; ++i) { if (a[i] == 0) ans = max(ans, init + postfix_zero[i + 2] - prefix_one[i]); else if (a[i] == 1) ans = max(ans, init + prefix_one[i] - postfix_zero[i + 2]); // } else { // NOTE: forgot 0->1 is possible // } } cout << ans << '\n'; } int main() { // {{{ cin.tie(nullptr)->sync_with_stdio(false); cin.exceptions(cin.failbit); int tc = 1; cin >> tc; for (int t = 0; t < tc; ++t) { solve(); } return 0; } // }}}