>[success] # 344. 反轉字符串 * 描述 編寫一個函數，其作用是將輸入的字符串反轉過來。輸入字符串以字符數組 s 的形式給出。 不要給另外的數組分配額外的空間，你必須原地修改輸入數組、使用 O(1) 的額外空間解決這一問題。 ? * 示例 1： ~~~ 輸入：s = ["h","e","l","l","o"] 輸出：["o","l","l","e","h"] ~~~ * 示例 2： ~~~ 輸入：s = ["H","a","n","n","a","h"] 輸出：["h","a","n","n","a","H"] ~~~ 來源：力扣（LeetCode） 鏈接：https://leetcode.cn/problems/reverse-string 著作權歸領扣網絡所有。商業轉載請聯系官方授權，非商業轉載請注明出處。 >[info] ## 對撞指針 * 指針從左右出發，進行對應值交換，當兩個指針相互對撞則結束  >[danger] ##### js ~~~ /** * @param {character[]} s * @return {void} Do not return anything, modify s in-place instead. */ var reverseString = function(s) { let right = s.length - 1 let left = 0 while(right >= left){ ;[s[left],s[right] ]=[s[right],s[left]] right -- left ++ } }; ~~~ >[danger] ##### java ~~~ class Solution { public void reverseString(char[] s) { int right = s.length-1; int left = 0; while(left < right){ char c = s[left]; s[left] = s[right]; s[right] = c; left++; right--; } } } ~~~