Problem C

Statement
Copy Copied
Description:
You are given a string $$$s$$$ consisting of $$$n$$$ lowercase Latin letters. Polycarp wants to remove exactly $$$k$$$ characters ($$$k \le n$$$) from the string $$$s$$$. Polycarp uses the following algorithm $$$k$$$ times:

- if there is at least one letter 'a', remove the leftmost occurrence and stop the algorithm, otherwise go to next item;
- if there is at least one letter 'b', remove the leftmost occurrence and stop the algorithm, otherwise go to next item;
- ...
- remove the leftmost occurrence of the letter 'z' and stop the algorithm.

This algorithm removes a single letter from the string. Polycarp performs this algorithm exactly $$$k$$$ times, thus removing exactly $$$k$$$ characters.

Help Polycarp find the resulting string.

Input Format:
The first line of input contains two integers $$$n$$$ and $$$k$$$ ($$$1 \le k \le n \le 4 \cdot 10^5$$$) β€” the length of the string and the number of letters Polycarp will remove.

The second line contains the string $$$s$$$ consisting of $$$n$$$ lowercase Latin letters.

Output Format:
Print the string that will be obtained from $$$s$$$ after Polycarp removes exactly $$$k$$$ letters using the above algorithm $$$k$$$ times.

If the resulting string is empty, print nothing. It is allowed to print nothing or an empty line (line break).

Note:
None