Score : $100$ points
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.
Input is given from Standard Input in the following format:
Print the amount of change as an integer.
We will use two $1000$-yen bills to pay the price and receive $100$ yen in change.
We can pay the exact price.