T = int(input())
for _ in range(T):
    N = int(input())
    H = list(map(int, input().split()))
    if H[0] < H[1]:
        print("No")
        continue
    c = 0
    t = False
    for i in range(1, N):
        if t == (H[i - 1] > H[i]):
            t = not t
            c += 1
    if c == 3:
        print("Yes")
    else:
        print("No")