做的练习题，输入整数，逆序输出，并输出位数。

public class Convert {
String input = "";
String output = "";
public void input_change(){
java.util.Scanner in = new java.util.Scanner(System.in);
System.out.println("请输入一个小于"+Long.MAX_VALUE+"的整数。");
long middle_number = in.nextLong();
input = middle_number + "";
System.out.println(input.length());
for(int a = 0; a < input.length(); a++){
output = input.charAt(a) + output;
}
System.out.println(output);
}
public static void main(String [] args){
Convert start = new Convert();
start.input_change();
}
}