Zebra puzzle: Difference between revisions

=={{header|Python}}==

<lang python>from itertools import permutations

import psyco; psyco.full()

class Number:elems= "One Two Three Four Five".split()

class Color: elems= "Red Green Blue White Yellow".split()

class Drink: elems= "Milk Coffee Water Beer Tea".split()

class Smoke: elems= "PallMall Dunhill Blend BlueMaster Prince".split()

class Pet: elems= "Dog Cat Fish Horse Bird".split()

class Nation:elems= "British Swedish Danish Norvegian German".split()

for c in (Number, Color, Drink, Smoke, Pet, Nation):

for i, e in enumerate(c.elems):

exec "%s.%s = %d" % (c.__name__, e, i)

def is_possible(number, color, drink, smoke, pet):

if number and number[Nation.Norvegian] != Number.One:

return False

if color and color[Nation.British] != Color.Red:

return False

if drink and drink[Nation.Danish] != Drink.Tea:

return False

if smoke and smoke[Nation.German] != Smoke.Prince:

return False

if pet and pet[Nation.Swedish] != Pet.Dog:

return False

if not number or not color or not drink or not smoke or not pet:

return True

for i in xrange(5):

if color[i] == Color.Green and drink[i] != Drink.Coffee:

return False

if smoke[i] == Smoke.PallMall and pet[i] != Pet.Bird:

return False

if color[i] == Color.Yellow and smoke[i] != Smoke.Dunhill:

return False

if number[i] == Number.Three and drink[i] != Drink.Milk:

return False

if smoke[i] == Smoke.BlueMaster and drink[i] != Drink.Beer:

return False

if color[i] == Color.Blue and number[i] != Number.Two:

return False

for j in xrange(5):

if (color[i] == Color.Green and

color[j] == Color.White and

number[j] - number[i] != 1):

return False

diff = abs(number[i] - number[j])

if smoke[i] == Smoke.Blend and pet[j] == Pet.Cat and diff != 1:

return False

if pet[i]==Pet.Horse and smoke[j]==Smoke.Dunhill and diff != 1:

return False

if smoke[i]==Smoke.Blend and drink[j]==Drink.Water and diff!=1:

return False

return True

def show_row(t, data):

print "%6s: %12s%12s%12s%12s%12s" % (

t.__name__, t.elems[data[0]],

t.elems[data[1]], t.elems[data[2]],

t.elems[data[3]], t.elems[data[4]])

def main():

perms = list(permutations(range(5)))

for number in perms:

if is_possible(number, None, None, None, None):

for color in perms:

if is_possible(number, color, None, None, None):

for drink in perms:

if is_possible(number, color, drink, None, None):

for smoke in perms:

if is_possible(number, color, drink, smoke, None):

for pet in perms:

if is_possible(number, color, drink, smoke, pet):

print "Found a solution:"

show_row(Nation, range(5))

show_row(Number, number)

show_row(Color, color)

show_row(Drink, drink)

show_row(Smoke, smoke)

show_row(Pet, pet)

print

main()</lang>

Output:

<pre>Found a solution:

Nation: British Swedish Danish Norvegian German

Number: Three Five Two One Four

Color: Red White Blue Yellow Green

Drink: Milk Beer Tea Water Coffee

Smoke: PallMall BlueMaster Blend Dunhill Prince

Pet: Bird Dog Horse Cat Fish</pre>