1100. Find K-Length Substrings With No Repeated Characters
Given a string S, return the number of substrings of length K with no repeated characters.
Input: S = "havefunonleetcode", K = 5
There are 6 substrings they are : 'havef','avefu','vefun','efuno','etcod','tcode'.
Input: S = "home", K = 5
Notice K can be larger than the length of S. In this case is not possible to find any substring.
1 <= S.length <= 10^4