Logic Programming
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Assignment - Zebra Puzzle


The Zebra puzzle is a classic logic puzzle. It is sometimes attributed to Albert Einstein and sometimes to Lewis Carroll. The version here is taken from Life International 1962.

There is a row of five houses.
The Englishman lives in the red house.
The Spaniard owns the dog.
Coffee is drunk in the green house.
The Ukrainian drinks tea.
The green house is immediately to the right of the ivory house.
The Old Gold smoker owns snails.
Kools are smoked in the yellow house.
Milk is drunk in the middle house.
The Norwegian lives in the first house.
The man who smokes Chesterfields lives in the house next to the man with the fox.
Kools are smoked in the house next to the house where the horse is kept.
The Lucky Strike smoker drinks orange juice.
The Japanese smokes Parliaments.
The Norwegian lives next to the blue house.

Your mission is to write a logic program that faithfully embodies these constraints and is capable of determining who owns the zebra. (No fair solving the puzzle yourself and building in the answer.)

A few points in the interest of clarity. Each of the five houses is painted a different color. The inhabitants are of different national extractions, own different pets, drink different beverages, and smoke different brands of American cigarettes. And, in statement 6, right means your right.