Problem: Many people are aware of DMCA – Digital Millennium Copyright Act. But another recently proposed DMCA – Digital Millennium Calculation Act – is much less known.

In this problem you need to find a root of a number according to this new DMCA law.

Input

The input contains a single integer a (1 ≤ a ≤ 1000000).

Output

Output the result – an integer number.

Examples

Input


1


Output


1


Input


81


Output


9

Solution (in JAVA):

Solution:
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.Scanner;
import java.util.*;
public class Main {
	static Scanner sc;
	public static void main(String[] args){
		sc = new Scanner(new BufferedReader(new InputStreamReader(System.in)));
        int n = sc.nextInt();
        int sum = 0;
        
        while(true) {
	        while(n != 0) {
	        	sum += n%10;
	        	n /= 10;
	        }
	        if(sum<10)break;
	        else {
	        	n = sum;
	        	sum = 0;
	        }
        }
       
        System.out.println(sum);
    }
 }