Project Euler is a popular list of programming problems. It was created in 2001 by Colin Hughes, and named after the famous mathematician Leonhard Euler.
The problem set varies in difficulty and it is very mathematical in its nature.
Due to this mathematical form I used haskell for solving them,
it gives a chance to use pure functional programming.
Haskell also plays very well with mathematical objects such as
fractions, infinite integers, infinite lists, lambda calculus...
Start GHCi from the src directory, load the problem that you want and call the solution without arguments from the haskell interpreter.
$ cd src
$ ghci
Prelude> :l e001.hs
[1 of 1] Compiling Main ( e001.hs, interpreted )
Ok, one module loaded.
*Main> solution
233168