Welcome to the 25th Beginners programming challenge.

This challenge is known by many different names. It is a logic puzzle that (according to some resources (unverified)) only est. 2% of the worlds population will be able to solve. Well, that assumption was made before computers were doing all the heavy lifting. I would now say that only 2% of programmers would be unable to brute force this puzzle


The challenge, should you choose to except it, is to write a solver for the Zebra Puzzle (aka, Einstein's Puzzle, Einstein's Riddle). The program, when run, should print the answer to the 2 questions at the end of the below quoted text.

Note: You are not expected to parse the text and computationally map out the issue before solving, I assume that you have read the rules and designed a program that, following those rules, and given facts, produces an answer to 2 questions.

  1. There are five houses.
  2. The Englishman lives in the red house.
  3. The Spaniard owns the dog.
  4. Coffee is drunk in the green house.
  5. The Ukrainian drinks tea.
  6. The green house is immediately to the right of the ivory house.
  7. The Old Gold smoker owns snails.
  8. Kools are smoked in the yellow house.
  9. Milk is drunk in the middle house.
  10. The Norwegian lives in the first house.
  11. The man who smokes Chesterfields lives in the house next to the man with the fox.
  12. Kools are smoked in the house next to the house where the horse is kept. [should be "... a house ...", see discussion below]
  13. The Lucky Strike smoker drinks orange juice.
  14. The Japanese smokes Parliaments.
  15. The Norwegian lives next to the blue house.

Now, who drinks water? Who owns the zebra? In the interest of clarity, it must be added that each of the five houses is painted a different color, and their inhabitants are of different national extractions, own different pets, drink different beverages and smoke different brands of American cigarets [sic]. One other thing: in statement 6, right means your right.
— Life International, December 17, 1962

Write a program that solve the zebra puzzle.
The program should output the answer to the questions:

  1. Who drinks water?
  2. Who owns the Zebra?

Cookie points

Cookie points will be awarded for the following extras

  1. The implementation of more than 1 algorithm for solving this (e.g. One brute force algorithm and 1 logic algorithm.)
  2. Solve these as well - http://en.wikipedia.org/wiki/Zebra_P...Other_versions

Disqualified Entries:

Any overly obfuscated code will be immediately disqualified without account for programmers skill. Please remember that these challenges are for beginners and therefore the code should be easily readable and well commented.

Any non-beginner entries will not be judged. Please use common sense when posting code examples. Please do not give beginners a copy paste solution before they have had a chance to try this for themselves.


If you require any help with this challenge please do not hesitate to come and chat to the development focus group. We have a channel on irc.freenode.net #ubuntu-beginners-dev
Or you can pm me

Have fun,
Happy coding

Ubuntu Beginners Team