#include<bits/stdc++.h>
using namespace std;
#define D(x) cerr<<__LINE__<<" : "<<#x<<" -> "<<x<<endl

const int MAX = 1e2+7;
long long a, b, h1, h2, H, jump, req, total;
string s;

int main() {
    cin>>s;
    total = s[0] - '0';
    while(s.length()>1) {
        total = 0;
        for(int i = 0; i<s.length(); i++) {
            total += s[i]-'0';
        }
        s = to_string(total);
    }
    cout<<total<<"\n";
}

### Prompt

Your challenge is to write a cpp solution to the following 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

### Response

```cpp
#include<bits/stdc++.h>
using namespace std;
#define D(x) cerr<<__LINE__<<" : "<<#x<<" -> "<<x<<endl

const int MAX = 1e2+7;
long long a, b, h1, h2, H, jump, req, total;
string s;

int main() {
    cin>>s;
    total = s[0] - '0';
    while(s.length()>1) {
        total = 0;
        for(int i = 0; i<s.length(); i++) {
            total += s[i]-'0';
        }
        s = to_string(total);
    }
    cout<<total<<"\n";
}

```