AT_abc423_a [ABC423A] Scary Fee

You have a bankbook from The Terrifying Bank. The deposit passbook of the bank has a terrifyingly scary property that the commission fee changes according to the withdrawal amount. To withdraw money from the passbook, you need to specify the withdrawal amount in units of $ 1\,000 $ yen, and pay a commission fee of $ C $ yen per $ 1\,000 $ yen of withdrawal amount separately from the balance. Withdrawals are not allowed if they would leave the balance below $ 0 $ yen. When the balance of your passbook from the bank is $ X $ yen, what is the maximum amount of money you can withdraw from it?

The input is given from Standard Input in the following format: > $ X $ $ C $

Output the answer.

### Sample Explanation 1 The commission fee required to withdraw $ 644\,000 $ yen is $ 644\,000 \times \displaystyle\frac{8}{1000} = 5\,152 $ yen, so since $ 644\,000 + 5\,152 \leq 650\,000 $ , you can withdraw $ 644\,000 $ yen. On the other hand, the commission fee required to withdraw $ 645\,000 $ yen is $ 645\,000 \times \displaystyle\frac{8}{1000} = 5\,160 $ yen, so since $ 645\,000 + 5\,160 > 650\,000 $ , you cannot withdraw $ 645\,000 $ yen. ### Sample Explanation 2 It is possible that no money can be withdrawn at all. ### Constraints - $ 1 \leq X \leq 10^7 $ - $ 1 \leq C \leq 999 $ - All input values are integers.