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.

Examples

Input

4 4 6

Output

5

Input

5 4 3

Output

0

Input

1 7 10

Output

0

Input

1 3 3

Output

1

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