f448() is another tabulation hashing function which maps two uint32_t to an uniform hash result of type uint64_t. This is useful to implement a skiplist based consistent hash ring with 2^64 possible ring slots (or positions).
f82() is hash function which hashes a unt64_t 8 byte unsigned integer key to a uint16_t 2 byte hash value. It belongs to the class of tabulation hashing functions and is perfect for implementing lock-less hash tables and other data structures that require an uniform and perfect distribution.
Skip lists are a probabilistic data structure that seem likely to supplant balanced trees as the implementation method of choice for many applications. Skip list algorithms have the same asymptotic expected time bounds as balanced trees and are simpler, faster and use less space.
When uniform random numbers are needed in C, just applying modulo is not enough. Whith using random() for portability and a few calculations this can be easily fixed.