Functional Programming Assignment: Hearts

Task : Implement an AI agent that plays a trick-based card game called Hearts.

• My implementation can be found in Player.hs
• The logics / strategies I used are discussed in Player.hs

Assignment Specs

The game of Hearts is a trick-taking game where the goal to score as few points as possible. All cards in the Hearts are worth one point, and the Queen of Spade is worth 13. Your task will be to implement a simple AI to beat other players (students and staff) at this game.

There will be two versions of the game:

1. A two-player version, which will be used to assess the strength of your player. This version will use calibrated opponents and can be seen as a test.
2. An online tournament where your player will be pitted against other AIs in four-player matches.

To play the game with your AI, you will need to implement a function called playFunc which will be given a number of parameters upon which you will need to act and return the card you believe will lead to victory. An important component of the game setup is that you will be allowed to have a form of memory.

Memory, in this case, will be entirely determined by you. The game will simply pass you information pertaining to the current round: your hand and other cards played; and the previous round: the complete set of cards played at the previous round and your memory.

The game you will play will follow most of the classic rules of Hearts. This game is very popular as it is easy to lean and play, thus many online versions are available if you want to train. Do note, though, that most of them usually vary a little, so take care to read the rules carefully.

At the core of the game of Hearts are the point cards: all cards in Hearts and the Queen of Spade. The goal of the game is to score as few points as possible. An alternative exists though: if a player manages to take all point cards, she gets 0 points and every other player gets 26 points (the maximum).

At the end of each round, when players have played all the cards in their hands, we tally the points in every trick taken by each player. That is, we sum the point cards they won.

The game goes on until at least one player has scored more than 100 points and there is exactly one player with the lowest score. The player with the lowest score is the winner.

Counting points in Hearts is done as follows:

1. Point cards: Each Hearts is worth 1 point, the Queen of Spades is worth 13 points.
2. Hand: At the end of each hand (players have played all their cards), each player receives the amount of points in the tricks they won.
3. Game: The game stops when a player has reached 100 points and exactly one other has the lowest score; the latter is the winner.

The rules of Hearts we will use are as follows:

1. Reneging: Each turn starts with a player playing a single card, the suit of which determines the suit of the trick. Other players must follow suit (play cards in the same suit) if they are able to; if they do not have any cards in that suit, they may discard any card of their choosing.
2. Bleeding: No point card may be played during the first round unless the player has no other choice.
3. Leading: The player with the Two of Clubs leads (starts) the first round with this card.
4. Breaking: No player may start a trick with a Heart before any has been played, unless they have no other choice.
5. Shooting the Moon: In case a player took all the point cards, she scores 0 points and the other players all score 26 points.