Problem Statement

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?

Constraints

• $1 \leq X \leq 10^7$
• $1 \leq C \leq 999$
• All input values are integers.

Sample Input 1Copy

650000 8

Sample Output 1Copy

644000

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 Input 2Copy

1003 4

Sample Output 2Copy

0

It is possible that no money can be withdrawn at all.

Sample Input 3Copy

10000000 24

Sample Output 3Copy

9765000