Puzzle | The Einstein’s Puzzle

Einstein’s puzzle is a famous logic puzzle that was supposedly created by Albert Einstein as a boy. The puzzle goes as follows:

There are five houses in a row, each with a different color. In each house lives a person of a different nationality. The five owners drink a certain type of beverage, smoke a certain brand of cigar, and keep a certain pet. No owners have the same pet, smoke the same brand of cigar, or drink the same beverage. We have to find out each of the respective persons with their respective belongings.

Pictorial representation of the puzzle

Here are the clues:

• The Brit lives in the red house.
• The Swede keeps dogs as pets.
• The Dane drinks tea.
• The greenhouse is on the immediate left of the white house.
• The owner of the greenhouse drinks coffee.
• The person who smokes Pall Mall rears birds.
• The owner of the yellow house smokes Dunhill.
• The man living in the center house drinks milk.
• The Norwegian lives in the first house.
• The man who smokes Blends lives next to the one who keeps cats.
• The man who keeps the horse lives next to the man who smokes Dunhill.
• The man who smokes Blue Master drinks beer.
• The German smokes Prince.
• The Norwegian lives next to the blue house.
• The man who smokes Blends has a neighbor who drinks water.

Solution:

Step 1: We need to arrange tables for every detail according to each house,

Tables for every detail according to each house

Step 2: We fill in the details of the color of the respective houses,

• House #5 can’t be green because it isn’t to the left of any house (see hint #4). 
• House #2 is blue because it is the only house next to the Norwegian (see hint#14), and from hint #9, we know that the Norwegian lives in house #1. 
• House #3 drinks milk (see hint#8), but we know the resident of the greenhouse drink coffee (see hint#5), so house #3 can’t be green. We are now left to choose between house #1 and house #4, but we know house #1 is to the left of the blue house (see second sentence of this section), and from hint #4, the greenhouse is to the left of a white house, not a blue one.
• Since we now know house #4 is green, we can infer by way of hint #4 that house #5 is white, because it is to whose left, green is located.
• Since there are 2 uncolored houses left (House #1, and House #3), we start with House #1. Well, that’s simple, the Norwegian lives there and from hint#1, the Brit lives in the red house. We conclude house #3 is Red.

Fill in the details of the color of the respective houses

Step 3: Filling in hints by looking at the clues,

Filling in hints by looking at the clues

Now, the only house next to the Dunhill smoker is the blue house.

The Dane isn’t the BlueMasters smoker, because the Dane drinks tea (see hint #3) while the BlueMasters smoker drinks beer (see hint #12). What all of this means is that either the Dane lives in house #5 and the BlueMasters smoker lives in house #2 or vice versa.

Trying the first scenario means the German and the Swede are left to both battle for house #4, which shouldn’t be.

Step 4: Looking for Who smokes what and their beverages, and pets!

• Next, we look at the Germans and the Swedes. Between the two of them, they now have house #4 and house #5 to choose from (House #2 is out of the question for the German, the Dane is already there.). The German smokes Prince (see hint #13), so he couldn’t be living in house #5.
• Per hint #15, the only place the Blend smoker could live is house #2. It is also clear who drinks water.
• We know what all houses smoke but the Brit, so the Brit is left to smoke Pall Mall. The only person who lives next to the Blend smoker, who hasn’t been assigned a pet is the Norwegian (see hint #10), so the Norwegian keeps cats.

  So the final matrix looks like this,

Final matrix

To summarize, we have,

Einstein’s Puzzle