1100. Find K-Length Substrings With No Repeated Characters

# 1100. Find K-Length Substrings With No Repeated Characters

## 刷题内容

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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 <= S.length <= 10^4