# [1704. Determine if String Halves Are Alike](https://leetcode.com/problems/determine-if-string-halves-are-alike/) ## 题目 You are given a string `s` of even length. Split this string into two halves of equal lengths, and let `a` be the first half and `b` be the second half. Two strings are **alike** if they have the same number of vowels (`'a'`, `'e'`, `'i'`, `'o'`, `'u'`, `'A'`, `'E'`, `'I'`, `'O'`, `'U'`). Notice that `s` contains uppercase and lowercase letters. Return `true` *if* `a` *and* `b` *are **alike***. Otherwise, return `false`. **Example 1:** ``` Input: s = "book" Output: true Explanation: a = "bo" and b = "ok". a has 1 vowel and b has 1 vowel. Therefore, they are alike. ``` **Example 2:** ``` Input: s = "textbook" Output: false Explanation: a = "text" and b = "book". a has 1 vowel whereas b has 2. Therefore, they are not alike. Notice that the vowel o is counted twice. ``` **Example 3:** ``` Input: s = "MerryChristmas" Output: false ``` **Example 4:** ``` Input: s = "AbCdEfGh" Output: true ``` **Constraints:** - `2 <= s.length <= 1000` - `s.length` is even. - `s` consists of **uppercase and lowercase** letters. ## 题目大意 给你一个偶数长度的字符串 s 。将其拆分成长度相同的两半,前一半为 a ,后一半为 b 。两个字符串 相似 的前提是它们都含有相同数目的元音('a','e','i','o','u','A','E','I','O','U')。注意,s 可能同时含有大写和小写字母。如果 a 和 b 相似,返回 true ;否则,返回 false 。 ## 解题思路 - 简单题。依题意,分别统计前半段元音字母的个数和后半段元音字母的个数,个数相同则输出 true,不同就输出 false。 ## 代码 ```go package leetcode func halvesAreAlike(s string) bool { return numVowels(s[len(s)/2:]) == numVowels(s[:len(s)/2]) } func numVowels(x string) int { res := 0 for _, c := range x { switch c { case 'a', 'e', 'i', 'o', 'u', 'A', 'E', 'I', 'O', 'U': res++ } } return res } ```