President

Goal

Get rid of all your cards as quickly as possible. The first to do so becomes president; the last one inherits the unenviable title of scum, which is what the game is called in Quebec French.

The cards

The whole 52-card deck is dealt. Ascending order: 3, 4, 5, 6, 7, 8, 9, 10, jack, queen, king, ace and 2, the strongest card. Suits do not matter.

How it works

• The player who leads plays a single card, a pair, a three of a kind (three cards of the same rank) or a four of a kind.
• In turn, clockwise, each player plays the same number of cards of a strictly higher rank, or passes. A player who passed may play again on their next turn if someone has played in the meantime.
• When all the other players pass in a row, the trick is swept away and the last player to have played leads again. Nothing beats a 2: the trick is swept away immediately.
• If that player has no cards left, the next player leads.

Roles and exchange

• Order of finishing: president, vice-president, neutral (with 5 or 6 players), vice-scum, scum.
• At the start of the next round, the scum gives their two best cards to the president, who gives back two of their choice. The vice-scum gives their best card to the vice-president, who gives one back.
• The scum deals and leads. In the first round, the player holding the 3 of clubs leads.

Scoring

In each round, every player earns 1 for each opponent who finished after them: with four players, the president earns 3 and the scum none. After the chosen number of rounds, the highest total wins; a tiebreaker round settles ties.

About the AI

Levels 1 to 3 follow increasingly refined rules of conduct: not breaking up pairs, keeping 2s, taking the lead back to go out, blocking an opponent about to finish. Levels 4 and 5 use Monte Carlo determinization: the AI generates many distributions of the hidden cards, consistent with the cards played and the exchanges (the president knows which cards they gave back and that the scum handed over their best ones), plays each round to the end and chooses the move that earns the most on average. The AI never sees your cards.