Socially distanced solvers

Online CS50 puzzle competition fosters remote collaboration

Jagat Kafle

Jagat Kafle of Nepal works on solutions to last year's CS50x Puzzle Day problems.

CS50x Puzzle Day may be an ideal team sport for a socially distanced world.

Since its inception in 2016, the annual event has been an online adaptation of the on-campus puzzle day that is part of the course Introduction to Computer Science (CS50), taught by David J. Malan, Gordon McKay Professor of the Practice of Computer Science.

The virtual competition gives everyone in the world the chance to form remote teams and tackle a series of logic problems (no computer science experience is needed.) The goal is to complete as many puzzles as possible before the end of the contest.

While online teams are the norm, with most Harvard students spending the spring term at home, this year’s competition could also be a golden opportunity for entire families living under one roof to participate together. 

Teams of two, three, or four are encouraged, but individuals can participate solo, as well. Nearly 9,000 people registered for last year’s CS50x Puzzle Day.

The game begins any time after midnight on Friday, April 3 (in the player’s time zone), and ends any time before 11:59 p.m. on Monday, April 6. Every team member needs to register at to participate.

If you are curious about what the competition entails, or want to practice, click here for last year’s puzzles and solutions.

Topics: Computer Science

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