B'You have a string s_1 s_2 ldots s_n and you stand on the left of the string looking right. You want to choose an index k ( 1 <= k <= n ) and place a mirror after the k -th letter, so that what you see is s_1 s_2 ldots s_k s_k s_{k - 1} ldots s_1 . What is the lexicographically smallest string you can see? A string a is lexicographically smaller than a string b if and only if one of the following holds: The first line of input contains one integer t ( 1 <= q t <= q 10 ,000 ): the number of test cases. The next t lines contain the description of the test cases, two lines per a test case. In the first line you are given one integer n ( 1 <= q n <= q 10^5 ): the length of the string. The second line contains the string s consisting of n lowercase English characters. It is guaranteed that the sum of n over all test cases does not exceed 10^5 . For each test case print the lexicographically smallest string you can see. In the first test case choose k = 1 to obtain "cc". In the second test case choose k = 3 to obtain "cbaabc". In the third test case choose k = 1 to obtain "aa". In the fourth test case choose k = 1 to obtain "bb". '...