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.