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 CPP):

Solution:
#include<bits/stdc++.h>
using namespace std;
int main(){
	string a;
	cin>>a;
	while(a.size()>1){
	int x=0;
	for( int i=0; i<a.size();i++){
		x+=a[i]-'0';
	}
	a=to_string(x);
	}
	cout<<a;
}