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CF1935A.Entertainment in MAC
Entertainment in MAC
Congratulations, you have been accepted to the Master's Assistance Center! However, you were extremely bored in class and got tired of doing nothing, so you came up with a game for yourself.
You are given a string and an even integer . There are two types of operations that you can apply to it:
- Add the reversed string to the end of the string (for example, if
cpm, then after applying the operationcpmmpc). - Reverse the current string (for example, if
cpm, then after applying the operationmpc).
It is required to determine the lexicographically smallest string that can be obtained after applying exactly operations. Note that you can apply operations of different types in any order, but you must apply exactly operations in total.
A string is lexicographically smaller than a string if and only if one of the following holds:
- is a prefix of , but ;
- in the first position where and differ, the string has a letter that appears earlier in the alphabet than the corresponding letter in .
Input
Each test consists of multiple test cases. The first line contains a single integer () — the number of test cases. The description of the test cases follows.
The first line of each test case contains a single even integer () — the number of operations applied to the string .
The second line of each test case contains a single string (), consisting of lowercase English letters, — the string to which the operations are applied.
Output
For each test case, output a single line — the lexicographically smallest string that can be obtained after applying exactly operations.
Note
In the first test case, you can apply the operation of the second type (i.e., reverse the string ) times. Then the string will remain equal to cpm.
In the second test case, you can do the following:
- Apply the operation of the second type, after which will become equal to
birg. - Apply operation of the first type (i.e., add the reversed string to the end of the string ), after which will become equal to
birggrib.
Samples
5
4
cpm
2
grib
10
kupitimilablodarbuz
1000000000
capybara
6
abacaba
cpm
birggrib
kupitimilablodarbuz
arabypaccapybara
abacaba
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