#1297
Maximum Number of Occurrences of a Substring
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hash table · string · sliding window
Description
Given a string s, return the maximum number of occurrences of any substring under the following rules:
- The number of unique characters in the substring must be less than or equal to maxLetters.
- The substring size must be between minSize and maxSize inclusive.
Example 1:
Input: s = "aababcaab", maxLetters = 2, minSize = 3, maxSize = 4
Output: 2
Explanation: Substring "aab" has 2 occurrences in the original string.
It satisfies the conditions, 2 unique letters and size 3 (between minSize and maxSize).
Example 2:
Input: s = "aaaa", maxLetters = 1, minSize = 3, maxSize = 3
Output: 2
Explanation: Substring "aaa" occur 2 times in the string. It can overlap.
Solution