Description

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

Example 1:

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

Example 2:

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

Constraints:

• 1 <= s.length <= 105
• s[i] is a printable ascii character.

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

Solution

• 앞서 풀었던 문제들과 비슷?하지만 난이도는 훨씬 낮았다. 타입이 스트링이라는 점만 달랐다.

public void reverseString3(char[] s) {
        int p = s.length - 1;
        for (int i = 0; i < s.length / 2; i++) {
            char temp = s[i];
            s[i] = s[p];
            s[p--] = temp;
        }
    }