java写法

利用两个StringBuffer，一个将小的字母存起来，另一个将大字母存起来，打印输出即可

import java.util.*;
public class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        String line = null;

        while(sc.hasNextLine()){
            line = sc.nextLine();
            StringBuffer sb1 = new StringBuffer();
            StringBuffer sb2 = new StringBuffer();
            char[] ch = line.toCharArray();
            for(int i=0;i<ch.length;i++){
                if(ch[i]>='A'&&ch[i]<='Z'){
                    sb1.append(ch[i]);
                }else{
                    sb2.append(ch[i]);
                }
            }
            System.out.println(sb2.toString()+sb1.toString());
        }
    }

}