According to the laws of the calendar, the ten digits in the calendar of "135780 wax, 3 1 day will never be bad, 469 winter is 30, February 28th in a normal year and February 29th in a leap year" will not appear: 5, 6, 7, 8 and 9. Every number will appear. A cube has only six faces (so it can only represent 0-5), but it can be disassembled and used on the back (so it can represent 6-9). So these numbers can represent calendars (is the landlord worried that single digits can't represent 0-9? ) can also be 1, 2, both cubes need one, and the other eight numbers can be conveniently placed on the other eight faces of the two cubes. This can represent a reference to any date: (/link? URL = k 1x efhrdl 4-jfkvrgf 1-qss 2 wjcvudiuurgj 36 u 3 bpte 1 wm7 EP 7 swua-vettb 12 napladpyk 4g-DCE bu 50 f 7 gofs s6j huyup 1 B3 VF 1 bq3 Xi)