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The Quiz

Solving Donald Knuth

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I thought it was about time for another head-scratcher. This one’s simple. Just replace each letter with a digit so that the addition works. The puzzle uses all ten digits, which is more than can be said for your humble editor, and the solution is unique.


All will be revealed next month. But I’m sure that by then you’ll have written a program in Erlang that solves all addition problems using the names of famous computer scientists. Or you’ll have devised the Google search expression that finds the answer online. So I’ll also reveal the author of the program that I used to construct this puzzle.