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;
#define ll long long

int main()
{
    ios_base::sync_with_stdio(0);
  cout.tie(0);
    ll n;
    cin>>n;
    if(n%9)cout<<n%9<<endl;
    else
        cout<<9<<endl;
    return 0;
}