algorithms
[DRAFT] Random Permutations With Constant Space
You want to iterate over a random ordering of items without storing or needing to lookup already-used items.
We can borrow an algorithm from cryptography called the Feistel Network to generate random permutations in constant
space and time. Applications include generating unique gift card codes or credit card numbers for your customers
without exposing already-generated codes/numbers, and efficiently implementing the fizzlefade effect from
Wolfenstein 3D.