The other day, I saw a really simple way to calculate the day of the week which minimizes (in my opinion) the amount of calculation done. Here's how it goes: First, there is a day of the week that is shared in common by April 4th (4/4), 6/6, 8/8, 10/10, 12/12, and a few others every year. Let's call this day "Doomsday". It is, of course, different every year, but in a single year all of the dates above will fall on the same day. It's really easy to remember: 4/4, 6/6, 8/8, 10/10, and 12/12 all fall on Doomsday. Now, remember "I go to my nine-to-five job at the seven-eleven". 5/9, 9/5, 7/11, and 11/7 all fall on Doomsday. 3/0 (The last day of February) falls on Doomsday. January and February take a little more practice to remember due to Leap Years. In ordinary years, 2/0 (the last day of January) and 1/3 fall on Doomsday; however, on Leap Years, 2/1 and 1/4 fall on Doomsday. So the list of "Doomsday" dates to remember are: 1/3 (or 4), 2/0 (or ...
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