import sys
from sys import stdin

TT = int(stdin.readline())

for loop in range(TT):

    N = int(stdin.readline())
    A = list(map(int,stdin.readline().split()))

    if A[0] != A[-1]:
        print ("Yes")
    else:

        flag = True

        f = A[-1]
        while A and A[-1] == f:
            del A[-1]

        A.reverse()
        while A and A[-1] == f:
            del A[-1]

        flag = False
        for i in range(len(A)-1):
            if A[i] == A[i+1]:
                flag = True

        if flag:
            print ("Yes")
        else:
            print ("No")