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
from sys import stdin
rr = lambda: stdin.readline().strip()
rrM = lambda: map(int,rr().split())
debug=0
if debug:
    fi = open('in.txt','r')
    rr=lambda: fi.readline().replace('\n','')

N,A,B = rrM()
smallest = A * (N-1) + B
largest = A + B * (N-1)
print max(0,largest - smallest + 1) if A<=B else 0
