# [3227] Vowels Game In A String ## 題目資訊 - **難度**: Medium - **標籤**: Math, String, Brainteaser, Game Theory - **題目連結**: https://leetcode.com/problems/vowels-game-in-a-string/ - **練習日期**: 2025-09-12 - **目標複雜度**: 時間 O(n)、空間 O(1) ## 題目描述 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`. ## 先備條件與限制 - 輸入限制:n ∈ [?, ?]、值域 ∈ [?, ?] - 回傳/輸出格式:... - 其他:是否允許排序/就地修改 ## 解題思路 ### 初步分析 - 類型:雙指針 / 滑動視窗 / 排序 / DP / 貪心 / 圖論 ... - 關鍵觀察: - 複雜度目標理由: ### 解法比較 1. 解法A(基準/暴力): - 思路: - 正確性: - 複雜度:O(?) / O(?) 2. 解法B(優化): - 思路: - 正確性: - 複雜度:O(?) / O(?) ### 乾跑(Dry Run) - 範例:... ### 常見陷阱 - 邊界:空/單一/極值/全相等 - 去重:排序後跳重複、集合 - 溢位:使用 64-bit ## 測試案例 ### 範例輸入輸出 ``` Input: ... Output: ... Explanation: ... ``` ### 邊界清單 - [ ] 空陣列/空字串 - [ ] 單一元素 / 全相同 - [ ] 含負數/0/大數 - [ ] 去重 - [ ] 大資料壓力 ## 複雜度分析 - 最壞:時間 O(?)、空間 O(?) ## 相關題目 / Follow-up - ## 學習筆記 - 今天學到: - 卡住與修正: - 待優化: --- **總結**:這題的核心在於 ______,適合練習 ______。