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>
#define ll long long int
using namespace std;
int main(){
	ll a;cin>>a;
	while(a/10){
		ll curr=0;
		while(a){
			curr=curr+a%10;
			a/=10;
		}
		a=curr;
	}
	cout<<a<<endl;
}