CF1496A.Split it!

传统题 时间 2000 ms 内存 256 MiB 4 尝试 1 已通过 1 标签

Split it!

Kawashiro Nitori is a girl who loves competitive programming.

One day she found a string and an integer. As an advanced problem setter, she quickly thought of a problem.

Given a string ss and a parameter kk, you need to check if there exist k+1k+1 non-empty strings a1,a2...,ak+1a_1,a_2...,a_{k+1}, such that $$s=a_1+a_2+\ldots +a_k+a_{k+1}+R(a_k)+R(a_{k-1})+\ldots+R(a_{1}).$$

Here++represents concatenation. We defineR(x)R(x)as a reversed stringxx. For exampleR(abcd)=dcbaR(abcd) = dcba. Note that in the formula above the partR(a_k+1)R(a\_{k+1}) is intentionally skipped.

Input

The input consists of multiple test cases. The first line contains a single integer tt (1≤t≤1001\le t\le 100)  — the number of test cases. The description of the test cases follows.

The first line of each test case description contains two integers nn, kk (1≤n≤1001\le n\le 100, 0≤k≤⌊n2⌋0\le k\le \lfloor \frac{n}{2} \rfloor)  — the length of the string ss and the parameter kk.

The second line of each test case description contains a single string ss of length nn, consisting of lowercase English letters.

Output

For each test case, print "YES" (without quotes), if it is possible to find a1,a2,…,ak+1a_1,a_2,\ldots,a_{k+1}, and "NO" (without quotes) otherwise.

You can print letters in any case (upper or lower).

Note

In the first test case, one possible solution is a1=qwa_1=qw and a2=qa_2=q.

In the third test case, one possible solution is a1=ia_1=i and a2=oa_2=o.

In the fifth test case, one possible solution is a1=dokidokiliteraturecluba_1=dokidokiliteratureclub.

Samples

7
5 1
qwqwq
2 1
ab
3 1
ioi
4 2
icpc
22 0
dokidokiliteratureclub
19 8
imteamshanghaialice
6 3
aaaaaa
YES
NO
YES
NO
YES
NO
NO

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