B"A permutation of length n is a sequence of integers from 1 to n of length n containing each number exactly once. For example, [1] , [4, 3, 5, 1, 2] , [3, 2, 1] are permutations, and [1, 1] , [0, 1] , [2, 2, 1, 4] are not. There was a permutation p[1 ... n] . It was merged with itself. In other words, let's take two instances of p and insert elements of the second p into the first maintaining relative order of elements. The result is a sequence of the length 2n . For example, if p=[3, 1, 2] some possible results are: [3, 1, 2, 3, 1, 2] , [3, 3, 1, 1, 2, 2] , [3, 1, 3, 1, 2, 2] . The following sequences are not possible results of a merging: [1, 3, 2, 1, 2, 3 ], [ 3, 1, 2, 3, 2, 1] , [3, 3, 1, 2, 2, 1] . For example, if p=[2, 1] the possible results are: [2, 2, 1, 1] , [2, 1, 2, 1] . The following sequences are not possible results of a merging: [1, 1, 2, 2 ], [ 2, 1, 1, 2] , [1, 2, 2, 1] . Your task is to restore the permutation p by the given resulting sequence a . It is guaranteed that the answer exists and is unique. You have to answer t independent test cases. The first line of the input contains one integer t ( 1 <= t <= 400 ) -- the number of test cases. Then t test cases follow. The first line of the test case contains one integer n ( 1 <= n <= 50 ) -- the length of permutation. The second line of the test case contains 2n integers a_1, a_2, ... , a_{2n} ( 1 <= a_i <= n ), where a_i is the i -th element of a . It is guaranteed that the array a represents the result of merging of some permutation p with the same permutation p . For each test case, print the answer: n integers p_1, p_2, ... , p_n ( 1 <= p_i <= n ), representing the initial permutation. It is guaranteed that the answer exists "...