After too many long days of home confinement, you may feel unable to face another jigsaw or crossword puzzle. Fear not. Harvard’s most popular course, Computer Science 50, has exactly what you need.
CS50 has become a phenomenon within and beyond the university, taught simultaneously at Yale (a first) and offered for free on the EdX education platform, where it’s the No. 1 course. The EdX version recently held its fifth annual Puzzle Day, which is actually four days, inviting teams from around the world to solve eight puzzles, none of which involve programming. Perhaps because so many people are stuck at home, the number of participants jumped 49% from last year to 13,427.
These eight problems are challenging. Really challenging. But they aren’t computer problems. A goal of the event is to emphasize that “computer science isn’t about programming but about problem-solving more generally,” says the course’s professor, David Malan. And they aren’t impossible; teams comprising 46% of participants submitted answers, and nearly all those teams answered at least some of the problems correctly.
Yes, there is an answer key, but we’re not giving it to you. You’ll fight longer and be more likely to solve a problem if finding the answer isn’t convenient. And if you eventually must surrender, you can at least take pride in finding the answer key online—though it isn’t all that hard.
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