Illuminations: One Hundred Forty Five Doors
One Hundred Forty Five Doors
A prisoner was thrown into a medieval dungeon with 145 doors. Nine, shown by black bars, are locked, but each one will open if before you reach it you pass through exactly 8 open doors. You don’t have to go through every open door but you do have to go through every cell and all 9 locked doors. If you enter a cell or go through a door a second time, the doors clang shut, trapping you.
The prisoner (in the lower right corner cell) had a drawing of the dungeon. He thought a long time before he set out. He went through all the locked doors and escaped through the last, upper left corner one.
What was his route?
Puzzle provided by Kordemsky: The Moscow Puzzles (Dover)
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One Hundred Forty Five Doors
A prisoner was thrown into a medieval dungeon with 145 doors. Nine, shown by black bars, are locked, but each one will open if before you reach it you pass through exactly 8 open doors. You don’t have to go through every open door but you do have to go through every cell and all 9 locked doors. If you enter a cell or go through a door a second time, the doors clang shut, trapping you.
The prisoner (in the lower right corner cell) had a drawing of the dungeon. He thought a long time before he set out. He went through all the locked doors and escaped through the last, upper left corner one.
What was his route?
Puzzle provided by Kordemsky: The Moscow Puzzles (Dover)
Problem and solution
What are you looking for?
Organization
Website URL
Type of Resource
PDF File