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 sys


def main():
    n, a, b = map(int, sys.stdin.readline().strip().split(" "))
    if a > b:
        print(0)
    elif a == b:
        print(1)
    else:
        if n == 1:
            print(0)
            return
        x = (n - 1) * a + b
        y = a + (n - 1) * b
        print(y - x + 1)


if __name__ == "__main__":
    main()
