#include <bits/stdc++.h>

using i64 = long long;
using u64 = unsigned long long;
using u32 = unsigned;

using u128 = unsigned __int128;
using i128 = __int128;

int main() {
    std::ios::sync_with_stdio(false);
    std::cin.tie(nullptr);

    int Q;
    std::cin >> Q;

    while (Q--) {
        int N;
        std::cin >> N;
        std::vector<int> A(N);
        std::vector<char> B, C = {'-', '+', '-', '+'};
        for (int i = 0; i < N; i++) {
            std::cin >> A[i];
        }
        for (int i = 1; i < N; i++) {
            int x = A[i] - A[i - 1];
            char c = '+';
            if (x < 0) c = '-'; 
            if (B.empty()) {
                B.push_back(c); 
            } else {
                if (B.back() != c) B.push_back(c);
            }
        }
        std::cout << (B == C ? "Yes\n" : "No\n");
    }

    return 0;
}