Thursday, January 15, 2009

Solving Contest 2008-01-27, ISC categ1 round1

The Fifth ISC (International Solving Contest) for 2009 is approaching, which takes place parallely in many countries at the same time.

We present, from the Fourth ISC (2008-01-27), the problems of the First Round of the First Category (difficult problems, with international rating) for you to practise.



Problems to be solved. (The solutions are at the end of this post).

(Problem 282)
M. Keller,
Second Prize, Saechsische Zeitung, 1985
Mate in 2.
#2 (13 + 6)
[8/1KQpp3/3P4/3RSP1S/2p1k1P1/2B5/BPs1PP2/3r4]


(Problem 283)
M. Feigl,
First Prize, Tourney KNSB, 1904,
Mate in 3.
#3 (8 + 9)
[KS5s/1Q6/1p1pk1Pp/2pR3S/5p2/1P4r1/4sP2/8]


(Problem 284)
H. Haefele,
Sixth Prize, Deutsche Schachzeitung, 1974,
Mate in 4.
#4 (10 + 9)
[4S1Ks/1r2p2p/1pSP1P2/1P1P1p2/2B1kp2/5p2/2P2B2/8]


(Problem 285)
O. J. Carlson,
Second Prize, Ajedrez, 1970,
White plays and stalemates.
= (3 + 4)
[8/8/2P5/8/2K5/2s5/6k1/rB4s]


(Problem 286)
R. Arnold,
harmonie, 2008
Helpmate in 3 moves. Two solutions.
h#3 2.1.1.1.1.1 (7 + 15)
[R7/8/2Pq3r/3ppsS1/p1s3P1/bp1Sk1pp/5pP1/Kb5r]


(Problem 287)
C. Gamnitzer,
First Prize ex aequo, feenschach, 2000,
Selfmate in 6 moves.
s#6 (9 + 9)
[1RK1kr2/1P3p1P/S2Q1pp1/1s3p2/BB2p3/7b/8/2R5]




The solutions of the problems

(Problem 282) M. Keller, Saechsische Zeitung, 1985, Second Prize

Tries : [1 Sd3? / f3+? Kxd5! / Ke3!],
[1 Sxd7? (if 1...Kxd5 (a) / exd6 (b) 2 Qc6# (A) / Sdf6# (B) ) Rxd5!],
[1 Sg6? (if 1...exd6 (b) / Rxd5 (c) 2 Shf6# (C) / Sg3# (D)) Kxd5!].
[1 Sf7? (if 1...Rxd5 (c) / Kxd5(a) 2 Sg5# (E) / Qxc4# (F)) exd6!],

Key : 1 Sxc4! (5) Kxd5 (a) / exd6 (b) / Rxd5 (c) 2 Sd2# (G) / f3# (H) / Sxd6# (I)


(Problem 283) M. Feigl, Tourney KNSB, 1904, First Prize

Tries : [1 Sc6? / Qc8+? / Qd7+? Kxd5!], [1 Re5+? Kxe5!], [1 Rd4? / Rf5? K(x)f5!], [1 Sg7+? Kf6!], [1 Sd7? Sxg6!], [1 Qf7+? Sxf7!], [1 Rxc5? dxc5!], [1 Rg5? Rxg5!], [1 fxg3? Sxg3!].

Key : 1 f3! ( > 2 Re5+ (1) dxe5 / Kxe5 3 Qd7# / Qe4#)
1...Sc3 2 Sc6 (1) Kxd5 / Sxd5 3 Sxf4# / Qc8#
1...Rxf3 2 Rg5 (1) hxg5 3 Qe4#
1...Rg5 2 Rxg5 (1) hxg5 3 Qe4#
1...Sxg6 2 Sg7+ (1) Kf6 3 Rf5#


(Problem 284) H. Haefele, Deutsche Schachzeitung, 1974, Sixth Prize.

Tries : [1 Sc7? Rxc7!], [1 fxe7? / d7? / dxe7? Rb8!], [1 Bd3+? Kxd5!], [1 fxe7? Rb8!].

Key : 1 Kg7! ( > 2 fxe7 Rxe7+ 3 dxe7 (0,5)
1...exf6+ 2 Kh6 Sf7+ / Rf7 3 Kh5 (0,5) / d7 (0,5)
1...exd6+ 2 f7 Rxf7+ 3 Kh6 (1)
1...e6+ 2 Kxh8 ( > 3 Bd3+ (0,5)) e5 3 Sb4 (0,5)
1...e5+ 2 Se7 Rxe7+ 3 fxe7 (1)
1...Rb8 2 Sc7 Rg8+ 3 Kxg8 (0,5)


(Problem 285) O. J. Carlson, Ajedrez, 1970, Second Prize

Key : 1 c7! Sa4 (not 1...Ra8? 2 Be4+ K~ 3 Bxa8 +-)
2 Be4+ (1) Sf3
3 Kb5 Rc1
4 Bc6 (1) Rc5+
5 Ka6 Rxc6+
6 Kb7 (1) Se5
7 c8=Q Sc5+
8 Kb8 Sed7+
9 Ka7 (1) Rg6
10 Qg8 = (1)


(Problem 286) R. Arnold, harmonie, 2008

Key : 1 Qb4! Se6 2 Ke4 Rxa4 3 Sce3 Sdc5# (2,5)

Key : 1 Qf6! Sxf2 2 Kf4 Rf8 3 Sfe3 Se6# (2,5)


(Problem 287) C. Gamnitzer, feenschach, 2000, First Prize ex aequo

Tries : [1 h8=S? Rxh8!], [1 Qe5+? fxe5!], [1 Qe6+? fxe6!], [1 Be1? / Bd2? / Bc3? / Rc5? Rg8!]

Key : 1 Rc4! ( > 2 Rxe4+ fxe4+ 3 Qd7+) Bg2,f1 (the bB leaves from the diagonal c8-h3)
2 Rc5 (interferes with wBb4 and > 3 Qe7+) Rg8 (the bR must become vulnerable)
3 h8=S ( > 4 Qe7+) Rg7 (now is evident why bPg6 was placed there)
4 Re5+ fxe5
5 Qe6+ fxe6
6 Sc7+ (5) Rc7#

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