Find the Longest Substring Containing Vowels in Even Counts
Given the string s, return the size of the longest substring containing each vowel an even number of times. That is, a, e, i, o, and u must appear an even number of times.
Example 1
Input
s = "eleetminicoworoep"Output
13The longest substring is "leetminicowor", which contains two each of the vowels e, i, and o and zero of the vowels a and u.
Example 2
Input
s = "leetcodeisgreat"Output
5The longest substring is "leetc", which contains two e's.
Constraints
- 1 <= s.length <= 5 x 10^5
- s contains only lowercase English letters.