Consider the following:

A string, $\boldsymbol{\mathrm{~S~}}$, of length $n$ where $s=c_0c_1\ldots c_{n-1}$.
An integer, $\boldsymbol{\mbox{k}}$, where $\boldsymbol{\mbox{k}}$ is a factor of $n$.

We can split $\boldsymbol{\mathrm{~S~}}$ into $\frac{n}{k}$ substrings where each subtring, $t_i$, consists of a contiguous block of $\boldsymbol{\mbox{k}}$ characters in $\boldsymbol{\mathrm{~S~}}$. Then, use each $t_i$ to create string $u_i$ such that:

The characters in $u_i$ are a subsequence of the characters in $t_i$.
Any repeat occurrence of a character is removed from the string such that each character in $u_i$ occurs exactly once. In other words, if the character at some index $j$ in $t_i$ occurs at a previous index $\lt j$ in $t_i$, then do not include the character in string $u_i$.

Given $\boldsymbol{\mathrm{~S~}}$ and $\boldsymbol{\mbox{k}}$, print $\frac{n}{k}$ lines where each line $\boldsymbol{i}$ denotes string $u_i$.

Example

$s=\text{'AAABCADDE'}$

$k=3$

There are three substrings of length $3$ to consider: 'AAA', 'BCA' and 'DDE'. The first substring is all 'A' characters, so $u_1=\text{'A'}$. The second substring has all distinct characters, so $u_2=\text{'BCA'}$. The third substring has $2$ different characters, so $u_3=\text{'DE'}$. Note that a subsequence maintains the original order of characters encountered. The order of characters in each subsequence shown is important.

Function Description

Complete the merge_the_tools function in the editor below.

merge_the_tools has the following parameters:

string s: the string to analyze
int k: the size of substrings to analyze

Prints

Print each subsequence on a new line. There will be $\frac{n}{k}$ of them. No return value is expected.

Input Format

The first line contains a single string, $\boldsymbol{\mathrm{~S~}}$.

The second line contains an integer, $\boldsymbol{\mbox{k}}$, the length of each substring.

Constraints

$1\leq n\leq10^4$, where $n$ is the length of $\boldsymbol{\mathrm{~S~}}$
$1\leq k\leq n$
It is guaranteed that $n$ is a multiple of $\boldsymbol{\mbox{k}}$.

Sample Input
STDIN Function
----- --------
AABCAAADA s = 'AABCAAADA'
3 k = 3

Sample Output
AB
CA
AD

Explanation

Split $\boldsymbol{\mathrm{~S~}}$ into $\frac{n}{k}=\frac{9}{3}=3$ equal parts of length $k=3$. Convert each $t_i$ to $u_i$ by removing any subsequent occurrences of non-distinct characters in $t_i$:

$t_0=\textsf{"AAB"}\to u_0=\textsf{"AB"}$
$t_1=\text{"CAA}\rightarrow u_1=\text{"CA}\text{"}$
$t_2=\text{"ADA}\text{"}\rightarrow u_2=\text{"AD}\text{"}$

Print each $u_i$ on a new line.

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