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 HelloWorld{

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