Most often they don't have any code. Most of the action takes place inside the head and not inside the computer. What they have are proofs of correctness, invar

Most often they don't have any code. Most of the action takes place inside the head and not inside the computer. What they have are proofs of correctness, invariant enforcement, complexity bounds etc. I doubt that reading the code will improve understanding of the algorithm anymore than a thorough description of the algorithm.