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 B {
    static Scanner scan = new Scanner(System.in);
    public static void main(String[] args) {
        int n = scan.nextInt();
        while(n > 9) {
            n = sum(n);
        }
        System.out.println(n);
    }
    public static int sum(int n) {
        int res = 0;
        while(n != 0) {
            res += n % 10;
            n /= 10;
        }
        return res;
    }
}