Thanks for the reply. Finaly I completed this Kata. I've read rules many times. And now completely changes my logic. 6 days I have played in another game...

Hi, it's not an issue. Frank can win at each of your cases. Please read again task and tip

Either I don't understand game's rules or there is really some kind of mistake.
Today I have faced these card combinations. They are all similar.
(Case 1
Frank: 3 5 8 9
Sam: 6 7 10 11
Tom: 0 1 2 4)
(Case 2
Frank: 1 2 5 8
Sam: 4 6 7 9
Tom: 0 3 10 11)
(Case 3
Frank: 3 4 5 7
Sam: 2 6 8 10
Tom: 0 1 9 11)
How Frank can win the game with these cards?

How Frank can win the game with these cards?
Frank: 2 3 4 8
Sam: 1 6 10 11
Tom: 0 5 7 9
If I understand rules and tips(about dumb moves) correctly, Frank will be able to win only one round but not the game. Thank you in advance for your response.

C#
I'm newbe. After 3 days of coding, I'm surprised to see one line solution. Yes I know, there are only three parts for solving the kata:
1)union of two arrays;
2)sorting;
3)removing of duplicated numbers;
First and second point I have completed for 10 minutes. The bigest problem for me was the removing of duplicated numbers.
Unfortunately I don't know algorithm for searching and removing of duplication. So who want to see my own algorithm which is using only FOR cicle and if/else". Welcome.