Difference between revisions of "Connect Four"

From CSE231 Wiki
Jump to navigation Jump to search
Line 70: Line 70:
  
 
{{Sequential|public double evaluate(Board board)}}
 
{{Sequential|public double evaluate(Board board)}}
 +
 +
Evaluate the current state of the board.  You should return a negative number if you have lost.  You should return less negative numbers for losses that occur later.
  
 
==OpenEndedHeuristic (Optional)==
 
==OpenEndedHeuristic (Optional)==

Revision as of 19:34, 30 April 2019

credit for this assignment: Finn Voichick and Dennis Cosgrove

Motivation

Minimax is an important concept in game theory and search.

Negamax is a variant which relies on

While this technique is applicable to Chess (as Deep Blue employed to defeat Kasparov), we choose Connect Four as our context since it has a simpler game mechanic.

While the core part of searches like Minimax may be easy to parallelize, critical aspects such as alpha-beta pruning are more challenging.

Background

Video

Tutorial

Solving Connect Four

Wikipedia

Minimax

Negamax

The Core Questions

  • What are the tasks?
  • What is the data?
  • Is the data mutable?
  • If so, how is it shared?

Code To Use

connectfour.core

interface Board

isDone()
getWinner()
getCurrentPlayer()
getTurnsPlayed()
createNextBoard(int column)


class EvaluationColumnPair

double getEvaluation()
Optional<Integer> getColumn()

java.util

class Optional<T>

Code To Implement

Negamax

class: ConnectFour.java Java.png
methods: select
negamaxKernel
selectNextColumn
package: connectfour.studio
source folder: student/src/main/java

method: private static ColumnEvaluationPair select(ColumnEvaluationPair[] array) Sequential.svg (sequential implementation only)

method: static ColumnEvaluationPair negamaxKernel(Board board, Heuristic heuristic, IntPredicate parallelPredicate, IntPredicate evaluatePredicate, int currentDepth) Parallel.svg (parallel implementation required)

method: public static int selectNextColumn(Board board, Heuristic heuristic, IntPredicate parallelPredicate, IntPredicate evaluatePredicate) Sequential.svg (sequential implementation only)

Win or Lose Heuristic

class: WinOrLoseHeuristic.java Java.png
methods: evaluate
package: connectfour.studio
source folder: student/src/main/java

method: public double evaluate(Board board) Sequential.svg (sequential implementation only)

Evaluate the current state of the board. You should return a negative number if you have lost. You should return less negative numbers for losses that occur later.

OpenEndedHeuristic (Optional)

class: OpenEndedHeuristic.java Java.png
methods: evaluate
package: connectfour.challenge
source folder: student/src/main/java

method: public double evaluate(Board board) Sequential.svg (sequential implementation only)

Testing Your Solution

Correctness

class: ConnectFourTestSuite.java Junit.png
package: connnectfour.studio
source folder: testing/src/test/java

Visualization

class: ConnectFourViz.java VIZ
package: connnectfour.viz.game
source folder: student/src//java

ConnectFourViz.png