There is a string s of length n containing lowercase letters and an integer k. Among the letters those appear exactly k times in string s, pick the lexicographically maximum one. Now delete any (k-1) occurrences of this letter from the string in a way so that the resultant string is lexicographically smallest.
Note that if there is no letter which appears k times in s, no deletion takes place.
What is the lexicographical smallest string after the deletions (possibly none)?
The first line of the input contains n (1 ≤ n ≤ 100000), the number of lowercase letters in string s and k (0 ≤ k ≤ 10).
The second line contains the string s.
Print the lexicographically smallest string after the deletions (possibly none).
5 2 baabc