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.io.*;
public class DMCA 
{
	public static void main(String[] args)throws IOException 
	{
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		int n=Integer.parseInt(br.readLine());
		int ans=0;
		while(n>0 || ans>9)
		{
			if(n==0)
			{
				n=ans;
				ans=0;
			}
			ans+=n%10;
			n/=10;
		}
		System.out.println(ans);
	}
}