面试题

import java.util.Scanner;
 
public class ReverseNumber {
	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		int n = in.nextInt();
		int a=0,c=0;
		int res=0;
		
		String s = n+"";
		int i=s.length()-1;
		if(n>=0) 
			a=1;
		else {
			a=-1;
			c=1;
		}
		for(;i>=c;i--){
			int b=s.charAt(i)-48;
			res = b+10*res;
		}
		System.out.println(res*a);
	}
}