/prisoners-dilemma

Go implementation of the Prisoner's Dilemma with various strategies

Primary LanguageGoMIT LicenseMIT

Prisoner's dilemma

Go implementation of the famous Prisoner's Dilemma.

Usage

Single game

To run a single game between two strategies:

go run main.go game <turns> <strategy1> <strategy2>

Where <turns> must be a positive integer. <strategy1> and <strategy2> must be chosen from (case insensitive):

  • AIID - Defects on every move.
  • AIIC - Cooperates on every move.
  • RAND - Makes a random move.
  • TFT - Cooperates on the first move, then copies the opponent’s last move.
  • GRIM - Cooperates, until the opponent defects, and thereafter always defects.
  • Pavlov - Cooperates on the first move. If a reward or temptation payoff is received in the last round then repeats last choice, otherwise chooses the opposite choice.
  • FBF - Cooperates on the first move, and cooperates except after receiving a sucker payoff.

For example:

$ go run main.go game 10 tft rand
TFT    moves:  [C C C D C C C D D C]
RAND   moves:  [C C D C C C D D C C]

TFT    scores: [3 3 0 5 3 3 0 1 5 3]
RAND   scores: [3 3 5 0 3 3 5 1 0 3]

TFT    total score: 26
RAND   total score: 26

IT'S A DRAW

Tournament

You can also run a tournament. Which means that every strategy plays against each other strategy, including itself.

Run

go run main.go tournament <turns>

For example:

go run main.go tournament 200
STRATEGY  SCORE

Pavlov    3444
AIIC      3088
AIID      2808
TFT       2646
FBF       2325
RAND      2006
GRIM      1325

Add a new strategy

To add a new strategy, you must follow these steps:

  • Implement the Strategy interface:
type Strategy interface {
	// Name of the strategy.
	Name() string

	// A description of the strategy.
	Description() string

	// in - the channel from which the strategy take the opponent's move.
	// out - the channel to which the strategy send its move
	// turns - the number of turns that the game will last
	Play(in chan Move, out chan Move, turns int)
}

  • Add the strategy to the TestStrategy in src/test/strategies_test.go function to test that the implementation is right.

  • Add the strategy to the array allStrategies in main.go to have it available in games and tournaments.