题解 | #字符串反转#

import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String str = scanner.next();
        char[] value = str.toCharArray();
        int n = value.length - 1;
        for (int j = (n - 1) >> 1; j >= 0; j--) {
            int k = n - j;
            char cj = value[j];
            char ck = value[k];
            value[j] = ck;
            value[k] = cj;
        }
        System.out.println(new String(value));
    }
}