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
N,A,B=map(lambda x:int(x) , raw_input().split(' '))

if N==0:
	print 0
elif N==1:
	if A==B:
		print 1
	else:
		print 0
elif A>B:
	print 0
else:
	print (B-A)*(N-2)+1
