# Re: Random Naughts and Crosses, Problem Search

From:
Daniel Pitts <newsgroup.spamfilter@virtualinfinity.net>
Newsgroups:
comp.lang.java.help
Date:
Sun, 10 Feb 2008 12:17:53 -0800
Message-ID:
<47af5baf\$0\$30522\$7836cce5@newsrazor.net>
Patricia Shanahan wrote:

Daniel Pitts wrote:

Patricia Shanahan wrote:

Mark Space wrote:

TheBigPJ wrote:

the large comparision if statement, but no one has a suitable
alternative.

Yeah that "if" is just nasty. I think you even missed one victory
condition. I count seven and there should be eight I think.
Replace it with a method that uses a loop to iterate over possible
victory conditions.

Also, consider making board a byte[3][3], reflecting the two-dimensional
geometry of the real board.

Actually, I would replace it with an 2d enum array.
enum Stroke {
EMPTY,
X,
O;
}
Or better yet, use a map instead:

final class Position {
final int x;
final int y;
public Position(int x, int y) {
this.x = x;
this.y = y;
}
public long hashCode() { return x + y * 37; }
public boolean equals(Object o) { return o instanceof Position &&
((Position)o).x == x && ((Position)o).y == y; }
}

In this situation, with sizes that have been fixed for centuries, in
what way is a map better than an array?

Patricia

It avoids primitive obsession. (Specifically the obsession with arrays)
Also, it is easier to set up than a list of lists :-)

You also can create a "Triplet" class that contains three position
objects. The Triplet class can have a strokesMatch method which returns
X, O, or null, depending on whether all the positions match the same
strokes.

--
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