Hash Divided String

You are given a string s of length n and an integer k, where n is a multiple of k. Your task is to hash the string s into a new string called result, which has a length of n / k.

First, divide s into n / k substrings, each with a length of k. Then, initialize result as an empty string.

For each substring in order from the beginning:

• The hash value of a character is the index of that character in the English alphabet (e.g., 'a' → 0, 'b' → 1, ..., 'z' → 25).
• Calculate the sum of all the hash values of the characters in the substring.
• Find the remainder of this sum when divided by 26, which is called hashedChar.
• Identify the character in the English lowercase alphabet that corresponds to hashedChar.
• Append that character to the end of result.

Return result.