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:
'a' → 0, 'b' → 1, ..., 'z' → 25).hashedChar.hashedChar.result.Return result.
Example 1:
Input: s = "abcd", k = 2
Output: "bf"
Explanation:
First substring: "ab", 0 + 1 = 1, 1 % 26 = 1, result[0] = 'b'.
Second substring: "cd", 2 + 3 = 5, 5 % 26 = 5, result[1] = 'f'.
Example 2:
Input: s = "mxz", k = 3
Output: "i"
Explanation:
The only substring: "mxz", 12 + 23 + 25 = 60, 60 % 26 = 8, result[0] = 'i'.
Constraints:
1 <= k <= 100k <= s.length <= 1000s.length is divisible by k.s consists only of lowercase English letters.