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;
typedef long long ll;
#define mod 1000000007

int main(){
    int n;cin>>n;
    int summ = 0;
    while(n>9){
        int summ = 0;
        while(n>9){
            summ = summ + n%10;
            n = n/10;
        }
        summ = summ + n;
        n = summ;
    }
    cout<<n;
    return 0;
}