Problem Description

Xiao Ming has just learned how to calculate the area of a rectangle. He found that if the length and width of a rectangle are both integers, its area must also be an integer. Now, Xiao Ming wants to know how many possible rectangles, with both length and width being integers, can have a given area. If two rectangles have the same length and the same width, they are considered the same rectangle. It is agreed that the length of the rectangle is greater than or equal to the width. A square is a special case of a rectangle, where the length and width can be equal.

Input Format

Input consists of a single line containing an integer $A$, which represents the area of the rectangle. It is guaranteed that $2 \leq A \leq 1000$.

Output Format

Output a single line containing an integer $C$, which represents the number of possible rectangles.

Sample Input and Output

Sample Input #1

4

Sample Output #1

2

Sample Input #2

6

Sample Output #2

2

Notes

Sample 1 Explanation

There are 2 rectangles with an area of 4, with dimensions 2x2 and 4x1.

Sample 2 Explanation

There are 2 rectangles with an area of 6, with dimensions 3x2 and 6x1.

见题面 Input 部分

见题面 Output 部分