There are many ways to order a list of integers from 1 to n. For example, if n = 3, the list could be : [3\; 1\; 2].

But there is a special way to create another list from the given list of integers. In this list, position of integer i is the i-th number in the given list. So following this rule, the given list will be written as: [2\; 3\; 1]. This list is called inverse list. Now there exists some list whose inverse list is identical. For example, inverse list of [1\; 2\; 3] is same as given list. Given a list of integers you have to determine whether the list is inverse or not.

The input contains several test cases. The first line is the number of test cases t (1 ≤ t ≤ 100) . The first line of each test case contains an integer n \;(1 ≤ n ≤ 100000). Then a list of the integers 1 to n follows in the next line.

SAMPLE INPUT
2
3
3 1 2
3
1 2 3

SAMPLE OUTPUT
not inverse
inverse

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