The third part of the first statement in the @Html.ActionLink("Zebra Problem", "Index") says, "inhabited by people of different nationalities".
This will be just like the @Html.ActionLink("door test", "Doors").
Let's select the house ID of the homes with the same nationality using LINQ.
Let's talk about this LINQ statement.
For each house in the Zebra Problem, grab a house and assert that all the other houses in the Zebra Problem don't have the same nationality.
If you find a house with the same nationality, stop, and write out a helpful message with the ID.
We can't compile because our House object does not have a nationality. Let's add it.
Now we add the Nationality enumeration.
We can compile, let's run the test.
1 test failed "A house was found with the same nationality as house 1."
There's a house with the same nationality as house 1. We have not assigned nationalities to the homes yet. The first house is ID 1, and all 5 homes have the same nationality (none).
Let's read ahead in the problem and identify all the possible nationalities. Then we can add them to our enumeration.
To get the test to pass we need to assign each house a unique nationality.
Let's run the tests again.
4 tests passed
Now, we need to do the same thing for: