Added first three solutions.
Modified formatting in 2 and 3.
Added solution to 5.
Adedd 6 and 8.
Added 16.
Added slow 4.
Added 17.
Added 17.
Added 13.
Added 15.
Fixed 13 and added 48.
Added slow 7.
Fixed 7 to use even function.
Added 20.
Moved most functions into modules.
Made 4 faster.
Added extremely slow 10.
Added somewhat slow 9.
Added 25.
Fixed choose function to use infix notation.