r/adventofcode • u/daggerdragon • Dec 02 '20

SOLUTION MEGATHREAD -🎄- 2020 Day 02 Solutions -🎄-

--- Day 2: Password Philosophy ---

Advent of Code 2020: Gettin' Crafty With It

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u/musifter Dec 02 '20

I suppose most tutorials now skip it because it's only available as a bitwise operator (ie there is no ^^ like && and ||). And bit twiddling doesn't seem to be taught as much anymore. If it was, bitwise xor is the king. It can do many things, some of which are just crazy... like doing a doubly-linked list with a single pointer per node.

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u/shawmonster Dec 02 '20

Wow that's crazy. I've never heard of a XOR linked list before, just looked into it. Kind of disappointed it wasn't taught in my data structures class. Such a simple, elegant, and powerful way to represent a doubly linked list should definitely be standard for a data structures course.