Alice initially has a string S of length N, and she decides to modify it! Her modification consists of K steps numbered from 1 to K. In the i-th step, Alice reverses the prefix of length i of S.

For example, suppose Alice starts with $S = \texttt{abferty}$, and she modifies it via 3 steps, then:
After the first step, $\textcolor{blue}{\texttt{a}}\texttt{bferty} \rightarrow S = \texttt{abferty}$
After the second step, $\textcolor{blue}{\texttt{ab}}\texttt{ferty} \rightarrow S = \texttt{baferty}$
After the third step, $\textcolor{blue}{\texttt{baf}}\texttt{erty} \rightarrow S = \texttt{faberty}$
So after $3 steps, her string becomes S = \texttt{faberty}$.

After performing her K-step modification, Alice ends up with the string S'. Now she challenges you to find the original string S. Can you do it?

------ Input Format ------

• The first line of the input contains a single integer T - the number of test cases. The test cases then follow.
• The first line of the test case contains two space-separated integers N and K - the length of the string and the number of steps in Alice's modification.
• The second line of the test case contains S' - the final string obtained after the modification.

------ Output Format ------

For each test case, output the original string S.

------ Constraints ------

$1 ≤ T ≤ 1000$
$1 ≤ N ≤ 10^{6}$
$1 ≤ K ≤ N$
$|S'| = N$
$S'$ contains only lowercase alphabets
- Sum of $N$ overall cases does not exceed $10^{6}$.

------ subtasks ------

Subtask $1$ (30 points): $1 ≤ N \cdot K ≤ 2000$
Subtask $2$ (70 points): Original constraints

----- Sample Input 1 ------
3
7 3
faberty
7 5
bbaaaba
4 4
zxwy

----- Sample Output 1 ------
abferty
aababba
wxyz

----- explanation 1 ------
- Test case $2$: The modification steps from $S$ to $S'$ is as follow:
- $1$-st step: $\textcolor{blue}{\texttt{a}}\texttt{ababba} \rightarrow S = \texttt{aababba}$
- $2$-nd step: $\textcolor{blue}{\texttt{aa}}\texttt{babba} \rightarrow S = \texttt{aababba}$
- $3$-rd step: $\textcolor{blue}{\texttt{aab}}\texttt{abba} \rightarrow S = \texttt{baaabba}$
- $4$-th step: $\textcolor{blue}{\texttt{baaa}}\texttt{bba} \rightarrow S = \texttt{aaabbba}$
- $5$-th step: $\textcolor{blue}{\texttt{aaabb}}\texttt{ba} \rightarrow S = \texttt{bbaaaba}$
- Test case $3$: The modification steps from $S$ to $S'$ is as follow:
- $1$-st step: $\textcolor{blue}{\texttt{w}}\texttt{xyz} \rightarrow S = \texttt{wxyz}$
- $2$-nd step: $\textcolor{blue}{\texttt{wx}}\texttt{yz} \rightarrow S = \texttt{xwyz}$
- $3$-rd step: $\textcolor{blue}{\texttt{xwy}}\texttt{z} \rightarrow S = \texttt{ywxz}$
- $4$-th step: $\textcolor{blue}{\texttt{ywxz}} \rightarrow S = \texttt{zxwy}$

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