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.Scanner;

public class B {
    public static void main(String[] args) {
        Scanner kb = new Scanner(System.in);
        int a = kb.nextInt();
        while(a>=10)
        {
            int m=a,x=0;
            while(m>0)
            {
                x+=m%10;
                m/=10;
            }
            a=x;
        }
        System.out.println(a);
    }
}