Bob the ghost has recently been going out to spook trick-or-treaters! Today, Bob has decided to target one poor victim with ~N~ candies. Bob spooks the victim ~a~ times, and each time the target is spooked, they lose ~b~ candies. How many candies does Bob's victim have left by the end of the day?

Input Specification

There will be ~1~ line of input containing three space-separated integers ~N, a, b~.

Output Specification

Output one integer, indicating the number of candies that the victim keeps.

Constraints

~1 \leq N \leq 10^6~

~0 \leq a \leq 10^3~

~0 \leq b \leq 10^3~

~N \geq ab~

Sample Input

15 3 4

Sample Output

3

Sample Explanation

Bob's victim starts with ~15~ candies, and loses ~3 \times 4~ candies, leaving ~3~ candies left over.