254. Maximum Number of Vowels in a Substring of Given Length

Given a string s and integer k, return the maximum number of vowel letters (a, e, i, o, u) in any contiguous substring of length k. Input: '"s", k'.

Input: '"s", k'.

Output: Integer — maximum vowel count.

Examples

Example 1

Input: "abciiidef", 3
Output: 3
Explanation: 'iii' has 3 vowels.

Example 2

Input: "aeiou", 2
Output: 2
Explanation: Any window of 2 vowels.

Example 3

Input: "leetcode", 3
Output: 2
Explanation: 'eet' or 'ode' has 2 vowels.