Problem Statement

Print a number between $A$ and $B$ (inclusive) that is a multiple of $C$.

If there is no such number, print -1.

Constraints

• $1 \\leq A \\leq B \\leq 1000$
• $1 \\leq C \\leq 1000$
• All values in input are integers.

Input

Input is given from Standard Input in the following format:

$A$ $B$ $C$

Output

Print the answer.
If there is no number with the desired property, print -1.

Sample Input 1

123 456 100

Sample Output 1

200

300 or 400 would also be accepted.

Sample Input 2

630 940 314

Sample Output 2

-1