B'You had a sequence a_1, a_2, ldots, a_n consisting of integers from 1 to n , not necessarily distinct. For some unknown reason, you decided to calculate the following characteristic of the sequence: Each test consist of multiple test cases. The first line contains a single integer t ( 1 <= t <= 10^4 ) -- the number of test cases. The description of 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 lost sequence a . The second line of each test case contains n integers r_1, r_2, ldots, r_n ( i <= r_i <= n+1 ) -- the characteristic of the lost sequence a . It is guaranteed that the sum of n over all test cases does not exceed 2 cdot 10^5 . For each test case, output the following: In the first test case, the sequence a = [1, 2, 1] is suitable. The integers 1 and 2 appear on the subsegments [1, 2] and [2, 3] . In the second test case, it can be proved that there is no suitable sequence a . '...