Calculating weekdays and dates with Go

Stage Fright

The preparations are complete, and your training program can begin! Advanced students are also welcome to extend the program by training for several changing years with different Doomsdays. If you want to simulate the time pressure that a magician experiences in front of an impatient audience, you can add a progress bar [3] to the game as an additional stress factor; this leaves the candidate only a short time to choose the day of the week. If the time expires, the score drops to zero points, which you could even accompany by a game show klaxon sound by playing an appropriate sound file. Enjoy!


  1. "Perl Script Reveals Math Trick" by Mike Schilli, Linux Magazine, issue 87, February 2008, p. 80
  2. Doomsday rule:
  3. "Develop a DIY Progress Bar" by Mike Schilli, Linux Magazine, issue 220, March 2019, pp. 46-49
  4. Listings for this article:
  5. Leap second:

The Author

Mike Schilli works as a software engineer in the San Francisco Bay area, California. Each month in his column, which has been running since 1997, he researches practical applications of various programming languages. If you email him at he will gladly answer any questions.

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