字符串逆序

 

 

 

import java.util.*;
 
public class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        String in = sc.nextLine();//不能用next();这个会以空格分割输入
        //将字符串分隔成字符存于字符数组中,然后做相互替换
        char ss[] =  new char[in.length()];
        //双指针，反向遍历将字符放进字符串中
        for(int i = ss.length-1,j=0;i>=0;i--,j++){
            ss[j] = in.charAt(i);
        }
        System.out.println(new String(ss));
    }
}