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.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.StringTokenizer;


public class TaskA {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		FastReader sc = new FastReader();
		PrintWriter out = new PrintWriter(System.out);
		int test = 1;
	
		while(test-->0) {
			long a = sc.nextLong();
			
			long summ = 0;
			if(a%9==0)summ = 9;
			else summ = a%9;
			out.println(summ);
		}
		
		out.close();
	}
	static class FastReader {
		
		StringTokenizer st;
		BufferedReader br;
		
		public FastReader() {
			br = new BufferedReader(
					new InputStreamReader(System.in));
		}
		
		String next() {
			while(st==null || !st.hasMoreElements()) {
				try {
					st = new StringTokenizer(br.readLine());
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			return st.nextToken();
		}
		
		int nextInt() {
			return Integer.parseInt(next());
		}
		
		long nextLong() {
			return Long.parseLong(next());
		}
		
		double nextDouble() { 
			return Double.parseDouble(next()); 
		} 
		
		String nextLine() {
			String s = "";
			while(st==null || st.hasMoreElements()) {
				try {
					s = br.readLine();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			return s;
		}
	}
}