3227 - Vowels Game in a String.

Medium

Alice and Bob are playing a game on a string.

You are given a string s, Alice and Bob will take turns playing the following game where Alice starts first:

• On Alice's turn, she has to remove any non-empty substring from s that contains an odd number of vowels.

• On Bob's turn, he has to remove any non-empty substring from s that contains an even number of vowels.

The first player who cannot make a move on their turn loses the game. We assume that both Alice and Bob play optimally.

Return true if Alice wins the game, and false otherwise.

The English vowels are: a, e, i, o, and u.

Example 1:

Input: s = "leetcoder"

Output: true

Explanation: Alice can win the game as follows:

• Alice plays first, she can delete the underlined substring in <code>s = "<ins> leetco </ins>der"</code> which contains 3 vowels. The resulting string is s = "der".

• Bob plays second, he can delete the underlined substring in <code>s = "<ins> d </ins>er"</code> which contains 0 vowels. The resulting string is s = "er".

• Alice plays third, she can delete the whole string <code>s = "<ins>er</ins>"</code> which contains 1 vowel.

• Bob plays fourth, since the string is empty, there is no valid play for Bob. So Alice wins the game.

Example 2:

Input: s = "bbcd"

Output: false

Explanation: There is no valid play for Alice in her first turn, so Alice loses the game.

Constraints:

• <code>1 <= s.length <= 10⁵</code>

• s consists only of lowercase English letters.