344. Reverse String

題目

Write a function that reverses a string. The input string is given as an array of characters char[].

Do not allocate extra space for another array, you must do this by modifying the input array in-place with O(1) extra memory.

You may assume all the characters consist of printable ascii characters.

Example 1:

Input: ["h","e","l","l","o"]
Output: ["o","l","l","e","h"]

Example 2:

Input: ["H","a","n","n","a","h"]
Output: ["h","a","n","n","a","H"]

題目大意

題目要求我們反轉一個字符串。

解題思路

這一題的解題思路是用 2 個指針，指針對撞的思路，來不斷交換首尾元素，即可。

來源

• https://books.halfrost.com/leetcode/ChapterFour/0300~0399/0344.Reverse-String/
• https://leetcode-cn.com/problems/reverse-string/

解答

https://github.com/kimi0230/LeetcodeGolang/blob/master/Leetcode/0344.Reverse-Stringm/Reverse-String.go

package reversestring

func ReverseString(s []byte) {
    for i, j := 0, len(s)-1; i < j; i, j = i+1, j-1 {
        s[i], s[j] = s[j], s[i]
    }
}