Problem Statement

Snuke has $N$ integers. Among them, the smallest is $A$, and the largest is $B$. We are interested in the sum of those $N$ integers. How many different possible sums there are?

Constraints

• $1 ≤ N,A,B ≤ 10^9$
• $A$ and $B$ are integers.

Input

Input is given from Standard Input in the following format:

N A B

Output

Print the number of the different possible sums.