Analytical Reasoning With Prolog

Last year, I solved the following analytical reasoning problem by hand. Post learning Prolog, I think this is a good problem to solve using a computer! I had a interesting experience doing so.

Problem:

Facts:

1: There are 5 villas in 5 different colors 

2: In each villa lives a person with a different nationality. 

3: These 5 owners drink a certain beverage, smoke a certain brand of cigar and keep a certain pet. 

4: No owner has the same pet, smoke the same brand of cigar or drink the same drink.

Hints:

1: The British lives in a red villa. 

2: The Swede keeps dogs as pets 

3: The Dane drinks tea 

4: The green villa is on the left of the white villa (it also means they are next door to each other) 

5: The green villa owner drinks coffee 

6: The person who smokes Pall Mall rears birds 

7: The owner of the yellow villa smokes Dunhill 

8: The man living in the villa right in the center drinks milk 

9: The Norwegian lives in the first villa 

10: The man who smokes Blend lives next to the one who keeps cats 

11: The man who keeps horses lives next to the man who smokes Dunhill 

12: The owner who smokes Blue Master drinks beer 

13: The German smokes Prince 

14: The Norwegian lives next to the blue villa 

15: The man who smokes Blend has a neighbor who drinks water.

The question is: who keeps the fish?

Prolog Solution:

The following is what i could come up with after serval iterations through code.

Answer to Puzzle:

Following is the output of the prolog program.

1,norwegian,yellow,water,dunhill,cat

2,dane,blue,tea,blend,horse

3,british,red,milk,pallmall,birds

4,german,green,coffee,prince,fish

5,swede,white,beer,bluemaster,dog

Hence the answer is German keeps the fish.