#include <bits/stdc++.h>
using namespace std;
int main()
{
    int n;
    cin>>n;
    int r=n%1000;
    cout<<(1000-r)%1000;
}

### Prompt

Your challenge is to write a cpp solution to the following problem:

We will buy a product for N yen (the currency of Japan) at a shop.

If we use only 1000-yen bills to pay the price, how much change will we receive?

Assume we use the minimum number of bills required.

Constraints

* 1 \leq N \leq 10000
* N is an integer.

Input

Input is given from Standard Input in the following format:


N


Output

Print the amount of change as an integer.

Examples

Input

1900


Output

100


Input

3000


Output

0

### Response

```cpp
#include <bits/stdc++.h>
using namespace std;
int main()
{
    int n;
    cin>>n;
    int r=n%1000;
    cout<<(1000-r)%1000;
}

```