A businessman has two cubes on his desk. Each cube has a number on each of its sides. Every day, the businessman arranges the cubes in such a way that the upward facing numbers display the day's date.
(Note that both cubes are always used for this, so on the 7th of the month, the cubes' surfaces display "07".)

How are these cubes numbered? (I.E. What numbers are on which cube? - call them C_{1} and C_{2}.)

(*From http://www.ocf.berkeley.edu/~wwu/riddles/intro.shtml*)

my parents have one of theese, however i restrain from looking at it.

soo here it is

0: one occorance (once it gets to ten it will be out of the ones)

1: two occurances (11 could happen)

2: two occurances (22 could happen)

3: one occurance (33 is more than 31, the highest number of days in a month)

4:one occurance (44 couldent happen)

5: one occurance

6: one occurance

7: one occurance

8: one occurance

9: one occurance

this makes, a total of twleve numbers needed, smaller ones on one cube, larger numbers on the other. it all works out.