Warning
This repository contains spoilers to various Project Euler problems.
Python solutions for various Project Euler problems. So far, I've incorporated the matching HackerRank problem into (almost) all problems. In some cases, such as problem 23, the HackerRank version differs from the original problem so much that I simply created a new function. Moreover, the Hackerrank version may not work out of the box and some memoization is required for the program to pass the test cases. For example, in problem 39 one would need to compute the results beforehand, together with the rolling argmaximum. Some problems were also done by hand, in which case the exact approach is detailed in the function description.
For now, there is no desire to use any external packages such as numpy to speed up computation. This may change in the future, however, if a lot of matrix computations are necessary.
- Problem 66: amounts to solving a handful of Pell equations. As such, the problem can be easily solved by using algebraic number theory.
- Problem 91: has a surprising closed form.
- Problem 94: surprising relation to some Pell equation, yielding a recurrence relation that completely solves the problem.
- Problem 96: I have never really programmed an algorithm for solving a sudoku, but it was surprisingly fun!
- Problem 100: similar connection to a Pell equation as 94.
- Testcase 10 of problem 29 in HackerRank does not work.
- Few testcases of problem 50 in HackerRank do not work (inefficient?)
- Wrong answers in problem 70 of HackerRank.
- Check other solutions of problem 88.
- New method in problem 61 does not work for all HackerRank test cases.
- HackerRank versions of 29, 32, 33, 34, 38, 43, 47, 48, 49, 51, 52, 59, 60, 68, 85.
- Problem 60 works and is within the one-minute rule, yet it still takes 16 seconds. Can it be optimized?
- Benchmarking?
- Update utilities and use a different algorithm for factoring such as SQUFOF. Moreover, divide utilities into multiple files, i.e factoring and generating inside different files.