Tech WondersPlay

Algorithms & EmergenceRecursion

The Tower of Hanoi

Moving 64 disks would take longer than the universe has existed

Three pegs and a few disks: a toy for children. So why would finishing the big version take longer than the universe has existed?

You'll find out

  • The one trick that solves any tower
  • Why one more disk doubles the work
  • Where else this pattern hides

Why it matters

This is how programmers think: crack a big problem by solving a smaller copy of it first.

About 3 min6 interactive slides · 5 questionsLesson 76 · Zone 9

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