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
def solve() :
  ar = raw_input().split()
  N = int(ar[0])
  A = int(ar[1])
  B = int(ar[2])

  if(A > B) : return 0
  if(N == 1 and A != B): return 0

  mn = A * (N-1) + B
  mx = A + B * (N-1)
  count = mx - mn + 1

  return count

if __name__ == '__main__' :
  print solve()