#include<bits/stdc++.h>

using namespace std;

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

### Prompt

Develop a solution in CPP to the problem described below:

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;

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

```