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.util.*;
public class Main
{
    static int check(int n)
    {
        int ans=0;
        while(n!=0 || ans>9)
        {
            if(n==0)
            {
                n=ans;
                ans=0;
            }
            ans=ans+n%10;
            n=n/10;
        }
        return ans;
    }
	public static void main(String[] args) {
	Scanner sc=new Scanner(System.in);
	int n=sc.nextInt();
	System.out.println(check(n));
	}
}