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()
{
    int x;
    cin>>x;
    while(x>=10)
    {
        int sum = 0;
        while(x)
        {
            sum+=x%10;
            x/=10;
        }
        x=sum;
    }
    cout<<x<<'\n';
    return 0;
}