Project Euler
Solve hard math problems by writing programs that find the answer
Project Euler is a long list of math problems that you solve with code. Each problem asks for a single answer. The first one, for example, asks for the sum of all multiples of 3 or 5 below 1000. Early problems are simple, but most need both a math idea and a program to find the answer.
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About Project Euler
Solving one problem often teaches a concept that opens up harder ones later. It suits programmers who like math, and students who want to practice algorithms. The archive holds more than 1,000 problems.
The site is free. You can read the problems without an account, but you need one to track your progress. You solve them on your own computer in any language you like.
On Breakpoint since 23 Oct 2026.