B"An array [b_1, b_2, ldots, b_m] is a palindrome, if b_i = b_{m+1-i} for each i from 1 to m . Empty array is also a palindrome. An array is called kalindrome, if the following condition holds: It's possible to select some integer x and delete some of the elements of the array equal to x , so that the remaining array (after gluing together the remaining parts) is a palindrome. Note that you don't have to delete all elements equal to x , and you don't have to delete at least one element equal to x . For example : You are given an array [a_1, a_2, ldots, a_n] . Determine if a is kalindrome or not. The first line contains a single integer t ( 1 <= t <= 10^4 ) -- the number of test cases. The description of the test cases follows. The first line of each test case contains a single integer n ( 1 <= n <= 2 cdot 10^5 ) -- the length of the array. The second line of each test case contains n integers a_1, a_2, ldots, a_n ( 1 <= a_i <= n ) -- elements of the array. It's guaranteed that the sum of n over all test cases won't exceed 2 cdot 10^5 . For each test case, print YES if a is kalindrome and NO otherwise. You can print each letter in any case. In the first test case, array [1] is already a palindrome, so it's a kalindrome as well. In the second test case, we can choose x = 2 , delete the second element, and obtain array [1] , which is a palindrome. In the third test case, it's impossible to obtain a palindrome. In the fourth test case, you can choose x = 4 and delete the fifth element, obtaining [1, 4, 4, 1] . You also can choose x = 1 , delete the first and the fourth elements, and obtain [4, 4, 4] . "...