You are given a string word and an integer k.

A string is considered $k$ special if the absolute difference between the frequencies of any two characters appearing in the string is at most $k$. That is, $|freq(c_1) - freq(c_2)| \leq k$ for any two characters $c_1$ and $c_2$ present in the string, where $freq(c)$ represents the number of occurrences of character $c$.

Return the minimum number of characters that must be deleted from word to make it $k$ special.

Constraints:

• $1 \leq$ word.length $\leq 10^5$

• $0 \leq$ k $\leq 10^5$

• word consists only of lowercase English letters.

Now, let’s take a moment to make sure you’ve correctly understood the problem. The quiz below helps you check if you’re solving the correct problem:

We have a game for you to play. Rearrange the logical building blocks to develop a clearer understanding of how to solve this problem.

Implement your solution in the following coding playground.