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
import fileinput

iterator = fileinput.input()

n, a, b = map(int, iterator.next().split())

def compute(n, a, b):
    # edge cases
    if n == 0:
        return 0
    if n == 1:
        if a == b:
            return 1
        else:
            return 0
    if a > b:
        return 0

    return (b - a) * (n - 2) + 1

print compute(n, a, b)
