1297 - Maximum Number of Occurrences of a Substring.

Medium

Given a string s, return the maximum number of ocurrences 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 ocurrences 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.

Constraints:

• <code>1 <= s.length <= 10⁵</code>

• 1 <= maxLetters <= 26

• 1 <= minSize <= maxSize <= min(26, s.length)

• s consists of only lowercase English letters.