给你一个由小写字母组成的长度为n的字符串 S ,找出所有长度为 k 且包含重复字符的子串,请你返回全部满足要求的子串的数目。
数据范围: ,
进阶: 时间复杂度,空间复杂度
class Solution: def numKLenSubstrRepeats(self , s , k ): # write code here count = 0 l = 0 while l+k <= len(s): sub = s[l:l+k] # 检查是否有重复字符 repeated = False d = {} for ch in sub: if ch in d: repeated = True break else: d[ch] = 1 if repeated: count += 1 l += 1 return count