# [Retros] Points

Eric Angelini Eric.Angelini at kntv.be
Sun Nov 27 17:05:19 EST 2016

```Nice problem indeed, François,
thanks -- and congratulations!

1.e3 b6 2.Qf3 Ba6 3.QxR BxB
4.QxN Bxg2 5.QxQ KxQ
à+
É.
Catapulté de mon aPhone

Le 24 nov. 2016 à 06:48, Eric Angelini <Eric.Angelini at kntv.be<mailto:Eric.Angelini at kntv.be>> a écrit :

Thanks François -- I will try to find
those 5 moves this w.-e. !
Best,
É.
Catapulté de mon aPhone

Le 24 nov. 2016 à 04:46, Francois Labelle <flab at wismuth.com<mailto:flab at wismuth.com>> a écrit :

Hi all,

Maybe we can formalize Eric's idea as the "net change in material value", where a capture causes a negative change, and (I propose) a promotion causes a positive change. For example, a queen promotion would be worth +8 (+9 for the queen, and -1 for the disappearing pawn). The standard valuation is 1,3,3,5,9 for P,N,B,R,Q.

-- Black has just long-castled at the

5th move, leaving 24 points out of

the board; what points?

[in other words, what pieces were

captured during the game, representing

a total amount of 24 points as explained

above]

According to my computer, the maximum net loss in material is indeed 24, but the captured pieces are not unique as the captured knight can be white or black:

1. e4 Nc6 2. Qg4 d5 3. Qxc8 Qxc8 4. Nh3 Qxh3 5. gxh3 O-O-O
1. e4 Na6 2. Qg4 d6 3. Qxc8 Qxc8 4. Bxa6 Qf5 5. exf5 O-O-O

Without the O-O-O constraint, the maximum is 30 and the solution turns out to be unique (I mean the game is unique, not just the identity of the captured pieces), so maybe this is a nicer problem:

"Find a game in 5.0 moves with a net loss in material of 30 points"

François

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