July 2015
Intermediate to advanced
286 pages
6h 31m
English

Imagine traversing a maze, and you come to a branch in the passage. Both paths loop around and meet up again a short distance later, but the passage to the left is blocked by a pool of molten lava. The passage to the right has no lava but is much longer than the other. Which path will get you to the exit faster?
Well, it depends, of course. But for normal people with no special lava resistance, taking the path without the lava is probably going to be optimal, even though it’s longer. The path with the lava, though shorter, is more expensive.
Costs like these are called weights. Distance itself is a form of weight, because ...