题解 | #数字颠倒#

利用字符串裁剪函数。
substring

import java.util.*;
public class Main {
    public static void main(String [] args){
        getNumber();
    }

    public static void getNumber(){
        Scanner scan = new Scanner(System.in);
        String input = scan.nextLine();
        int len = input.length();
        Map<String,String> map = new HashMap<>();
        String ret = "";
        for(int i = len-1; i >= 0; i--){
            ret += input.substring(i,i+1);
        }
        System.out.print(ret);
    }
}