Packing squares

As many squares with side $c$ as possible were packed into a rectangle with sides $a$ and $b$. The squares do not overlap, are not rotated, and their sides are parallel to the sides of the rectangle. How many squares fit, and how much of the rectangle's area stays empty?

A single line with three integers $a$, $b$, $c$ ($1 \le a, b, c \le 10^9$).

A single line with two integers: the number of squares and the empty area.

Along side $a$ there fit $a / c$ squares and along side $b$ there fit $b / c$ (integer division). In the first example: $(5 / 2) \cdot (10 / 2) = 2 \cdot 5 = 10$ squares, empty area .