Score : $100$ points
Takahashi loves takoyaki - a ball-shaped snack.
With a takoyaki machine, he can make at most $X$ pieces of takoyaki at a time, taking $T$ minutes regardless of the number of pieces to make.
How long does it take to make $N$ takoyaki?
Input is given from Standard Input in the following format:
$N$ $X$ $T$
Print an integer representing the minimum number of minutes needed to make $N$ pieces of takoyaki.
20 12 6
He can make $12$ pieces of takoyaki in the first $6$ minutes and $8$ more in the next $6$ minutes, so he can make $20$ in a total of $12$ minutes.
Note that being able to make $12$ in $6$ minutes does not mean he can make $2$ in $1$ minute.
1000 1 1000
It seems to take a long time to make this kind of takoyaki.