There are four problems for contestants:

• Problem 1. Contestant should fix code in Unit Tests. CUT is correct. It can be wrong Mock setup, async void, etc.
• Problem 2. Contestant should fix code in CUT. Unit Tests are correct. In CUT you can find such mathematical functions as factorial, triangle inequality, prime number and number of digits.
• Problem 3. Contestant should fix code in CUT. Unit Tests are correct. In CUT override of Equals and GetHashCode should be added.
• Problem 4. Contestant should fix code in CUT. Unit Tests are correct. IN CUT Deconstruct method parameters should be in correct position.