Quiz 51: Find titles required to cover the ground

Problem:

Given a rectangular ground of dimension X by Y. And we have square tiles of size A by A. Find minimum number of tiles required to cover the ground.
Note: Tiles cannot be broken, it is OK if titles crosses rectangle boundary.

Input Format: 

X Y A

Output Format: 
Number of tiles

Constraints: 
None

Sample Input

8 10 4

Sample Output:
6

Explanations:
8 x 8 will be covered by 4 titles of 4 x 4. Remaining area 8 x 2 will be covered by another 2 tiles. So total 6 tiles.

---

Solution:

chomp($line=<STDIN>);
($x,$y,$p)=split(" ",$line);
if($x%$p==0)
{
$tmp1=$x/$p;
}
else
{
$tmp1=int($x/$p)+1;
}
if($y%$p==0)
{
$tmp2=$y/$p;
}
else
{
$tmp2=int($y/$p)+1;
}
$ans=$tmp1*$tmp2;
print $ans;

---

Tips:

check x, y for divisibility by a and code accordingly