It may take you days to solve today's Brain Game. In fact, I guarantee that it will, because it's about calendars. Suppose you're a craftsman that likes to print calendars using wooden blocks. You've designed a grid exactly like this one:

calendarNow, it's time for you to carve the wood blocks that will represent the dates. You want to create one printing block for each possible space on the calendar, including blanks. Considering how calendars vary from month-to-month and year-to-year...

How many different blocks would you have to carve
to fit inside the above grid to handle ALL possible months

Here is the SOLUTION.


FORTY in all. The calendar would require:

  • 31 blocks for the numbers 1 through 31
  • 2 "split date" blocks reading "23/30" and "24/31" (for 31-day months beginning on Friday, or 30- or 31-day months beginning on Saturday, see sample below)
  • 7 "blank" blocks (all would be used in a non-leap-year February)

August 2009 sample