Explanation

Student A believes that his lucky number is the largest number that can be divided by $K$among non negative integers that do not exceed $N$. Can you help him calculate his lucky number?

Input format

Input - line, containing two integers $N$,$K$($1 ≤ N, K ≤ 2 × 10 ^ 9$).

Output format

Output - line, containing an integer representing a lucky number.

Example

3 2

2