CF1935A.Entertainment in MAC
普及/提高-
通过率:0%
AC君温馨提醒
该题目为【codeforces】题库的题目,您提交的代码将被提交至codeforces进行远程评测,并由ACGO抓取测评结果后进行展示。由于远程测评的测评机由其他平台提供,我们无法保证该服务的稳定性,若提交后无反应,请等待一段时间后再进行重试。
题目描述
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 s and an even integer n . There are two types of operations that you can apply to it:
- Add the reversed string s to the end of the string s (for example, if $s = $ cpm, then after applying the operation $s = $ cpmmpc).
- Reverse the current string s (for example, if $s = $ cpm, then after applying the operation $s = $ mpc).
It is required to determine the lexicographically smallest † string that can be obtained after applying exactly n operations. Note that you can apply operations of different types in any order, but you must apply exactly n operations in total.
† A string a is lexicographically smaller than a string b if and only if one of the following holds:
- a is a prefix of b , but a=b ;
- in the first position where a and b differ, the string a has a letter that appears earlier in the alphabet than the corresponding letter in b .
输入格式
Each test consists of multiple test cases. The first line contains a single integer t ( 1≤t≤500 ) — the number of test cases. The description of the test cases follows.
The first line of each test case contains a single even integer n ( 2≤n≤109 ) — the number of operations applied to the string s .
The second line of each test case contains a single string s ( 1≤∣s∣≤100 ), consisting of lowercase English letters, — the string to which the operations are applied.
输出格式
For each test case, output a single line — the lexicographically smallest string that can be obtained after applying exactly n operations.
输入输出样例
输入#1
5 4 cpm 2 grib 10 kupitimilablodarbuz 1000000000 capybara 6 abacaba
输出#1
cpm birggrib kupitimilablodarbuz arabypaccapybara abacaba
说明/提示
In the first test case, you can apply the operation of the second type (i.e., reverse the string s ) 4 times. Then the string s will remain equal to cpm.
In the second test case, you can do the following:
- Apply the operation of the second type, after which s will become equal to birg.
- Apply operation of the first type (i.e., add the reversed string s to the end of the string s ), after which s will become equal to birggrib.