mit.ai.techniques
Class LinePossibilities

java.lang.Object
  |
  +--mit.ai.techniques.LinePossibilities

public class LinePossibilities

extends java.lang.Object

This class computes all the possible assignments that can satisfy the constraints for one row or column of the puzzle. It stores all the possibilities in an internal Vector, each is an array of booleans.

Field Summary

private java.util.Vector

possibilities

Constructor Summary

LinePossibilities(java.util.Vector blockLengths, int lineSize)
Given the lengths of the blocks in a puzzle line, generate all possible locations of the blocks.

Method Summary

boolean[]	elementAt(int index) Retrieve a possibility.
private boolean[]	lineVariables(int numBlocks, int lineSize, java.util.Vector blockLengths, int[] blockLocations) Given a placement of blocks in a line and the sizes of the lines, generate a boolean array indicating which squares are occupied.
private void	locateBlocks(int currentBlock, int firstAvailableLocation, int numBlocks, int lineSize, java.util.Vector blockLengths, int[] blockLocations) Recursively assign blocks to locations.
int	size() How many possibilities exist?

Methods inherited from class java.lang.Object

, clone, equals, finalize, getClass, hashCode, notify, notifyAll, registerNatives, toString, wait, wait, wait

Field Detail

possibilities

private java.util.Vector possibilities

Constructor Detail

LinePossibilities

public LinePossibilities(java.util.Vector blockLengths,
                         int lineSize)

Given the lengths of the blocks in a puzzle line, generate all possible locations of the blocks. We'll create a vector of possibilities. Each possibility is an array of lineSize booleans, specifying which locations are occupied.

Method Detail

locateBlocks

private void locateBlocks(int currentBlock,
                          int firstAvailableLocation,
                          int numBlocks,
                          int lineSize,
                          java.util.Vector blockLengths,
                          int[] blockLocations)

Recursively assign blocks to locations. This procedure should be nested inside the constructor, but we can't do that in Java. Adds things on to possibilities.

lineVariables

private boolean[] lineVariables(int numBlocks,
                                int lineSize,
                                java.util.Vector blockLengths,
                                int[] blockLocations)

Given a placement of blocks in a line and the sizes of the lines, generate a boolean array indicating which squares are occupied.

size

public int size()

How many possibilities exist?

elementAt

public boolean[] elementAt(int index)

Retrieve a possibility. Black pixels are true, and white pixels are false.