Problem 180 Solution

Here is the solution. At the end of any step you may win, otherwise proceed to the next step.

  1. Pick two adjacent holes and turn both switches to on.
  2. Pick two opposite holes and turn both switches to on. Assuming I didn't win then I must have a DUUU configuration.
  3. Pick two opposite holes. If one switch is down turn up and win. Otherwise turn one down for a DDUU configuration.
  4. Pick two adjacent holes. If the switches are in the same position then switch both (and win). If different switch them for a DUDU configuration.
  5. Pick ossosite holes and switch both switches (and win).

Thanks to Stacy Friedman for this puzzle.

Michael Shackleford, A.S.A. - December 14, 2000