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:
/*
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 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
import java.util.*;

/**
 *
 * @author Shivam Patel
 */
public class Solution {

    public static void main(String args[]) {
        Scanner sc = new Scanner(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);
    }

}