SOLVE
LATER
Probably, you have already guessed that Benny doesn't like math at all. Especially, she is really bad at number theory.
Little Benny wants you to answer one single questions that disturbs her every night.
You will be given three integers: $$l$$, $$r$$, $$g$$. You have to output the number of pairs of integers $$x$$ and $$y$$ such that $$\gcd(x, y) = g$$ and $$l \leq x, y \leq r$$.
Note that pairs $$(1, 2)$$ and $$(2, 1)$$ are different.
Input format
The first line contains three integers $$l$$, $$r$$ and $$g$$
Constraints
$$1 \leq l, r, g \leq 10^9$$
$$0 \leq r-l \leq 10^3 \cdot g$$
Output format
Output single integer: the answer to the problem.
The following pairs formed the answer: $$(5, 5)$$, $$(5, 10)$$, $$(10, 5)$$. As you can see there are only three such pairs.