Leetcode - 反转字符串

技术思考者2025-08-02 23:02

反转字符串

编写一个函数，其作用是将输入的字符串反转过来。输入字符串以字符数组 s 的形式给出。

不要给另外的数组分配额外的空间，你必须原地修改输入数组、使用 O(1) 的额外空间解决这一问题。

示例 1：

输入：s = ["h","e","l","l","o"]

输出：["o","l","l","e","h"]

示例 2：

输入：s = ["H","a","n","n","a","h"]

输出：["h","a","n","n","a","H"]

提示：

1 <= s.length <= 105
s[i] 都是 ASCII 码表中的可打印字符

解答：

java 复制代码

public static void reverseString(char[] s) {
    int left = 0;
    int right = s.length - 1;
    while (left < right) {
        // 交换左右指针的字符
        char temp = s[left];
        s[left] = s[right];
        s[right] = temp;
        // 移动指针
        left++;
        right--;
    }
}