ZOJ Problem Set - 1476
A weird clock marked from 0 to 59 has only a minute hand. It won't move until
a special coin is thrown into its box. There are different kinds of coins as
your options. However once you make your choice, you cannot use any other kind.
There are infinite number of coins of each kind, each marked with a number d
( 1 <= d <= 1000 ), meaning that this coin will make the minute hand move
d times clockwise the current time. For example, if the current time is 45,
and d = 2. Then the minute hand will move clockwise 90 minutes and will be pointing
There are several tests. Each test occupies a line containing two positive
integers s and d.
For each test print in a single line the minimum number of coins needed. If it is impossible to turn the hand back to 0, output "Impossible".
Author: DU, Peng
Source: ZOJ Monthly, December 2002