# Find the Chessboard!

Philippe Schnoebelen, 20 Jun 1995

Here is a nice chess problem with no chessboard. Only cartesian coordinates
are given. The problem has a retro-flavor because the solver has to compute
the size of the chessboard and its orientation. (Yes, I'll post a solution
in a few days if nobody does it before,)

Eric Angelini
Europe Echecs, Nov 1990
----------------------------------------
| wK(0,0) wR(14,-2) wN(4,3) wB(0,5) |
| bK(5,0) bP(-2,-4) |
----------------------------------------
4+2. White mate in 3.

The author, <eric.angelini@infoboard.be>, has just subscribed to the
mailing list. He asks me whether I was aware of any similar problem, and
how original is this concept.

Why ask poor me? That is a question for you, the real retro-scholars on
the list!

### Philippe Schnoebelen, 22 Jun 1995

I'm back with some additional points regarding Eric Angelini's problem I
posted two days ago. (Thanks to Richard Sabey.)

phs> The problem has a retro-flavor because the solver has to compute
phs> the size of the chessboard and its orientation.

Well, some precisions may be in order: the orientation may well involve
*any* rotation, not necessarily a multiple of quarter-turns. Also the
coordinates do not necessarily assume that squares on the chessboard have
integer (or unit) length.

phs> Eric Angelini
phs> Europe Echecs, Nov 1990
phs> ----------------------------------------
phs> | wK(0,0) wR(14,-2) wN(4,3) wB(0,5) |
phs> | bK(5,0) bP(-2,-4) |
phs> ----------------------------------------
phs> 4+2. White mate in 3.

I make this clear not because I thought you might miss it :-) but because
it sheds a new light to the originality question: Who knows whether
problems with a similar idea already exist?

### Richard Sabey, 28 Jun 1995

Here's a chess problem like one which Eric Angelini posted a few days ago.
Only cartesian coordinates are given. You have to compute the size of the
chessboard and its orientation. I'll post a solution in a few days if
nobody does it before.

WK(0,1) WB(2,2) WN(0,2) WP(1,1) BK(1,0) #4

Apart from a minor dual I think that my intended solution is unique. How
many solutions can you find?