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() {
    long a, root=0;
    cin >> a;
    while(a!=0) {
        root += a%10;
        a /= 10;
    }
    root %= 9;
    if(root==0)
        root = 9;
    cout << root << endl;
    return 0;
}