101730: [AtCoder]ABC173 A - Payment

Problem Statement

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.

Sample Input 1

1900

Sample Output 1

100

We will use two $1000$-yen bills to pay the price and receive $100$ yen in change.

Sample Input 2

3000

Sample Output 2

0

We can pay the exact price.