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.*;
import java.util.*;
public class squareroot {
	public static void main (String [] args) throws IOException{
		  BufferedReader f = new BufferedReader(new InputStreamReader(System.in));
	      PrintWriter out = new PrintWriter(System.out);
	      StringTokenizer st = new StringTokenizer(f.readLine());
	      int next = Integer.parseInt(st.nextToken());
	      while (next>=10) {
				int sum=0;
				for (char c:(next+"").toCharArray()) {
					sum+=c-'0';
				}
				next=sum;
			}
			out.println(next);
			out.close();
		}
	}