I think it misses the XOR trick for bi-directional lists: https://en.wikipedia.org/wiki/XOR_linked_list https://en.wikipedia.org/wiki/XOR_linked_list They're r

I think it misses the XOR trick for bi-directional lists: https://en.wikipedia.org/wiki/XOR_linked_list https://en.wikipedia.org/wiki/XOR_linked_list They're really evil on modern CPUs.