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CF1634A.Reverse and Concatenate
Reverse and Concatenate
Real stupidity beats artificial intelligence every time.— Terry Pratchett, Hogfather, Discworld
You are given a string of length and a number . Let's denote by the reversed string (i.e. ). You can apply one of the two kinds of operations to the string:
- replace the string with
- replace the string with
How many different strings can you get as a result of performing exactly operations (possibly of different kinds) on the original string ?
In this statement we denoted the concatenation of strings and as . In other words, , where and are the lengths of strings and respectively.
Input
The first line contains one integer () — number of test cases. Next lines contain test cases:
The first line of a test case contains two integers and (, ) — the length of the string and the number of operations respectively.
The second string of a test case contains one string of length consisting of lowercase Latin letters.
Output
For each test case, print the answer (that is, the number of different strings that you can get after exactly operations) on a separate line.
It can be shown that the answer does not exceed under the given constraints.
Note
In the first test case of the example:
After the first operation the string can become either aabbaa or baaaab. After the second operation there are 2 possibilities for : aabbaaaabbaa and baaaabbaaaab.
Samples
4
3 2
aab
3 3
aab
7 1
abacaba
2 0
ab
2
2
1
1
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