Chef and Trump Cards

Chef is playing a card game with his friend Chefu. The rules of the game are as follows: - There are two piles of cards. One pile belongs to Chef and the other to Chefu. One pile may be empty. - At any moment, each card used in the game has a positive integer value. Whenever the value of a card becomes non-positive, it is removed from the game. - The game is played in rounds. In each round, eac