For Bill Raymond:
<<......but you wrote that FcPro produces mostly single-move solutions,
rarely two-card moves, maybe never more. But surely FcPro will employ longer
moves when useful.....>>
I meant the moves as expressed by the FcPro SOLVER, which are inherited
from the Don Woods solver. The moves that it will do for a player who
specifies a source and a destination are an entirely different matter. I
think we've to some degree been talking at cross purposes, in that you've
been concerned primarily with automatic moves to the foundation, and my
emphasis has been on providing convenience to the human player in making
column-to-column moves using the least required physical commands. Now that
I see what "Raymond's rule" is, I have to acknowledge that that's a very new
revelation to me. I need to give it some study. I've reallly thought up to
now that the Horne rule was the theoretical optimum and maximum, but maybe
you've got something there.
<<MS freecell allows for only two possibilities: move one card, move the
longest legal sequence. Nothing in between. In other words, some perfectly
legal moves are not usable in certain situations. >>
My contention would be that any such moves, where you want to move less
than the maximum number of cards from a column to an empty column, can
always be constructed by a series of single card moves. Such single card
moves would have to go via a route through a freecell. It is for this
reason that, in the design of FcPro, after initially copying Horne's
question which pops up whenever one attempts a move to an empty column that
could be either single or multiple cards, requring the player to choose
between the single and multiple card option, that we decided to eliminate
this interruption to play, which is an annoyance. The question was: Is it
an essential annoyance? I. e., might one be blocked off from a path that
would be essential to solving a deal by being prohibited from choosing the
single card option? Mike Keller and I both agreed that this would not be
the case, and the demonstration, or proof, is really rather simple. The
option only applies when at least one freecell is vacant, or when there
exists more than one empty column. So a freecell is always available, or
can be made available , as a temporary resting place for the single card
that one might wish to move to an empty column. I feel it's a virtual
certainty that the same logic would apply to moving more than one, but less
than the maximum, cards of a sequence into an empty column.
<<Aside: I suggest that it may be possible to create a legal freecell
position that is unsolvable because of that MS limitation.>>
That should be more than an "aside", because it's a critically important
issue. If that is true, then we have a very serious issue. I do not
believe that it is possible. If my line of argument above is correct in its
logic, then it would not be possible. I'll leave it to you to prove your
case. No, that's not the way to put it. Let's say, I'll leave it to you to
test your conjecture.
Best regards, ---------------Adrian
Received on Tue Dec 11 2001 - 05:44:30 IST