My solutions to some problems from Project Euler - some are in Objective-C and some are in Python. I haven't tested these in ages but they gave me the correct answers!
Have a look at their website: https://projecteuler.net
I have uploaded both the source code for the solutions and the "resources" required for some of the challenges (the files provided by the Project Euler website). I have not uploaded any libraries that might be required, or placed the resources in the correct locations - for now, this code is simply for reference (although feel free to try and run it if you wish - you'll need to install a couple of libraries and replace all the relevant file paths in the code, as well as creating an Xcode project for the Objective-C part).