Given two numbers N and P, find out how many numbers X exist such that N % X = P(where % is the remainder of the division of N with X).

**Input Format**

The only line of input contains two integers N and P separated by single space.

**Constraints**

- 1 <= P < N <= 1000000000

**Output Format**

Print the only line with the answer.

**Sample Input 0**

5 1

**Sample Output 0**

2

**Explanation 0**

The values of X are 2 and 4.

5 % 2 = 1 and 5 % 4 = 1.

My approach : iterate from 1 to a-1 and count

is the answer can be like this how many factors(except 1) of number (a-p) have ?

Help me with some good explanation and proof, (if possible).

@l_returns @ashokshaun @aryanc403