def ip():return int(input())
def mp():return map(int, input().split())
def lmp():return list(map(int, input().split()))
T = ip()
from collections import defaultdict
def solve():
    N = ip()
    A = lmp()
    cnt = defaultdict(int)
    cnt[A[0]] = 1
    for i in range(1, N):
        cnt[A[i]] += 1
        if A[i] != 1 and A[i] == A[i-1]:
            print('No')
            return
    if cnt[0] == 0 or cnt[2] == 0:
        print('No')
    else:
        print('Yes')
for _ in range(T):
    solve()