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.

 

Example 1:

Input: 

S = 
"havefunonleetcode"

, K = 
5

Output: 

6

Explanation: 

There are 6 substrings they are : 'havef','avefu','vefun','efuno','etcod','tcode'.

Example 2:

Input: 

S = 
"home"

, K = 
5

Output: 

0

Explanation: 

Notice K can be larger than the length of S. In this case is not possible to find any substring.

 

Note:

1. 1 <= S.length <= 10^4
2. All characters of S are lowercase English letters.
3. 1 <= K <= 10^4