The Zebra Puzzle

There are five houses.
The Englishman lives in the red house.
The Spaniard owns the dog.
The Japanese is an artist.
The Italian drinks tea.
The Norwegian lives in the first house (in the leftmost).
Coffee is drunk in the green house.
The green house is immediately to the right of the white house (right means your right.).
The sculptor owns snails.
The diplomat's house is yellow.
Milk is drunk in the middle house.
The Norwegian lives next to the blue house.
The violinist drinks orange juice.
The doctor lives in the house next to the man with the fox.
The diplomat's house is next to the house where the horse is kept.
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 have different professions.

Its solution in Prolog

l(1).
l(2).
l(3).
l(4).
l(5).
query :- l(English), l(Red), English=Red,
    l(Spanish), English\==Spanish, l(Dog), Spanish=Dog,
    l(Japanese), English\==Japanese, Spanish\==Japanese, l(Artist),
      Japanese=Artist,
    l(Italian), English\==Italian, Spanish\==Italian, Japanese\==Italian,
      l(Tea), Italian=Tea,
    Norwegian=1, English\==Norwegian, Spanish\==Norwegian, Japanese\==Norwegian,
      Italian\==Norwegian,
    l(Green), Red\==Green, l(Coffee), Tea\==Coffee, Green=Coffee,
    l(White), Red\==White, Green is White + 1,
    l(Sculptor), Artist\==Sculptor, l(Snails), Dog\==Snails, Sculptor=Snails,
    l(Diplomat), Artist\==Diplomat, Sculptor\==Diplomat, l(Yellow),
      Red\==Yellow, Green\==Yellow, White\==Yellow, Diplomat=Yellow,
    Milk=3, Tea\==Milk, Coffee\==Milk,
    l(Norwegian), l(Blue), Red\==Blue, Green\==Blue, White\==Blue,
      Yellow\==Blue, 1 is abs(Norwegian-Blue),
    l(Violinist), Artist\==Violinist, Sculptor\==Violinist,
      Diplomat\==Violinist, l(Juice), Tea\==Juice, Coffee\==Juice, Milk\==Juice,
      Violinist=Juice,
    l(Fox), Dog\==Fox, Snails\==Fox, l(Doctor), Artist\==Doctor,
      Sculptor\==Doctor, Diplomat\==Doctor, Violinist\==Doctor,
      1 is abs(Fox-Doctor),
    l(Horse), Dog\==Horse, Snails\==Horse, Fox\==Horse,
      1 is abs(Horse-Diplomat),
    l(Zebra), Dog\==Zebra, Snails\==Zebra, Fox\==Zebra, Horse\==Zebra, l(Water),
      Tea\==Water, Coffee\==Water, Milk\==Water, Juice\==Water,
    write('zebra lives at house #'), write(Zebra), write(' ('),
      (Zebra=English, X='English'; Zebra=Spanish, X='Spanish';
       Zebra=Japanese, X='Japanese'; Zebra=Italian, X='Italian';
       X='Norwegian'),
      write(X), write(')'), nl,
    write('water is drunk at house #'), write(Water), write(' ('),
      (Water=English, Y='English'; Water=Spanish, Y='Spanish';
       Water=Japanese, Y='Japanese'; Water=Italian, Y='Italian';
       Y='Norwegian'),
      write(Y), write(')'), nl.
:-initialization(query).