Monday, March 24, 2008

Symbols of Chessmen, Chess notation

The positions of the problems may be given with a diagram, with algebraic notation, or with Forsyth notation.

In diagrams, the eight columns (files) are named from left to right : a, b, c, d, e, f, g, h. The eight rows (ranks) are named from bottom to top: 1, 2, 3, 4, 5, 6, 7, 8.
There are 32 squares white and 32 squares black. Two adjacent squares in a column or in a row differ in colour. Every diagonal line has squares of the same colour. The lower left square is named a1 (column-a row-1) and is black.

The white have started from rows 1 & 2 and play upwards. The black have started from rows 8 & 7 and play downwards.

Symbols of the chessmen

White Black Chessman_greek french english german
KkΡ vassilias (=king)R RoiK KingK Koenig
QqΒ vassilissa (=queen)D DameQ QueenD Dame
RrΠ pirgos (=tower)T TourR RookT Turm
BbΑ axiomatikos (=officer)F FouB BishopL Läufer
SsΙ hippos (=horse)C CavalierKt KnightS Springer
PpΣ stratiotis (=soldier)P PionP PawnB Bauer

Let us see now a problem so we can visualize all this.

(Problem 1)
Samuel R. Barrett,
Dubuque Chess Journal, 1874
White plays and mates in 12 moves
#12 (5+3)

The black king is on column-a and the white king is on column-d. All the pawns are on row-2.
The white pawns are on their initial position and they are ready to move upwards. The black pawn in b2 is ready to be promoted on b1. White will find a way to prevent this, but he will need twelve moves to reach mate.
(This problem reminds me the slide of the playground.
The children climb up the ladder and then slide down.
Can you find the mechanism of the solution?
The complete solution is at the end of this post).

In the next diagram we see one of the oldest problem published by a Greek composer (Mr. Economopoulos E.) in the magazine "Nuova Rivista" in 1881, and was republished in the magazine “To Mat” (No.26, 15/01/1984).

(Problem 2)
Economopoulos E.,
“Nuova Rivista”, 1881
White plays and mates in 3 moves
#3 (5+1)

The position, the stipulation and the solution of the problem can be written in algebraic notation :

(Position:) White : Ka5, Ra8, Rf1, Bd5, Se6 (pieces 5). Black : Ke7 (piece 1).

(Stipulation:) White plays and mate in 3 moves.

(Solution:) Key: 1.Sd4!
if 1...Kd7 2.Sb5 Ke7 3.Rf7#
if 1...Kd6 2.Rd8+ Kc7 3.Se6#
or 2...Ke7 / Ke5 3.Sc6#

Let us read the solution, in favor of people who do not know the notation of the moves.
The stipulation states that white plays first and must mate in three moves.
The first move of the white is called key of the problem. The key is a unique move and is written with exclamation mark. Here the key is move of the knight, (symbol S), to square d4.
Black possess only their king, (and problems with this characteristic are called Rex solus : king alone), thus the various series of moves after the key (which are called variations) start with a move of the king.
If the black king, (symbol K), moves to d7, the second move of the white is knight to b5. The second move of the black king brings him to e7, where the third move of white, Rook (symbol R) goes to f7, gives mate (symbol #).
If black plays Kd6, white moves the rook to d8 and gives check (=threats the king, symbol +), the king move to c7, where is mated by the white’s third move, knight to e6. If, after the move 2 Rd8+, the black king tries to escape to e7 or to e5, then the third move of the white, knight to c6, gives mate.

Another form of short description of the position of a problem is the Forsyth notation (from the name of the Scott journalist David Forsyth of the 19th century). We start to scan the squares of the chessboard row by row, starting fro a8 to h8, continuing from a7 to h7, etc, until from a1 to h1, writing down the chessmen (with capital letters the white, with small letters the black) and also how many empty squares are in between. The change of row is denoted by a slash. With (w+b) we denote how many white and black pieces exist, and with #m we denote how many moves are required to reach the mate.

Using Forsyth notation the position of the problem-1 is given as follows:
[8/8/8/8/8/8/ppQKPPP1/k7] (5+3) #12
and the position of the problem-2 is given as follows:
[R7/4k3/4S3/K2B4/8/8/8/5R2] (5+1) #3

During solving contest, for orthodox problems, the last move of black and the last mating move of white is not necessary to be written. (For example, for two-movers only the key is required).

(We apply numbering on the problems we publish here, to help referencing in next post or comments.
The position in Forsyth notation is short and is usually readable from problem solving software.
Many problemists prefer to use german symbols for the chessmen of their problems).

The complete solution of problem-1 (Barrett) is:
Key: 1.Qc3!
(pins the pawn b2 to inhibit its promotion, thus only the king can move)
1...Kb1 2.Qd3+ Ka1
3.Qd4 Kb1 4.Qe4+ Ka1
5.Qe5 Kb1 6.Qf5+ Ka1
7.Qf6 Kb1 8.Qg6+ Ka1
9.Qg7 Kb1 10.Qh7+ Ka1
11.Qh8 Kb1 12.Qh1#
It seems that the moves are many, but the mechanism is simple: pin-check-pin-check etc. The climbing of the queen to the top of the ladder is quite impressive.

As solution for problem-2 (Economopoulos) it is enough to write on the solutions sheet :
1.Sd4! Kd7 / Kd6 2.Sb5 / Rd8+

[This Post in Greek language]

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