Problem:
How Many Divisors?

Write a program which reads three integers a, b and c, and prints the number of divisors of c between a and b.

Input

Three integers a, b and c are given in a line separated by a single space.

Output

Print the number of divisors in a line.

Constraints

1 ≤ a, b, c ≤ 10000

a ≤ b

Sample Input 1

5 14 80

Sample Output 1

3

Solution in Ruby (judge verdict: Runtime Error)

require 'prime'
a,b,c=gets.split.map(&:to_i)
d=c.prime_division.map{|e,n|0.step(n).map{|i|e**i}}
p d.shift.product(*d).map{|e|e.reduce(:*)}.count{|e|a<=e&&e<=b}