Problem Display
PID: 5058 (8/2B2p2/8/1pk2P1p/4QN1R/8/n7/2n2K2 w - - 0 1)

Challenger, Alfred Clement

Knowledge, 1898

8/2B2p2/8/1pk2P1p/4QN1R/8/n7/2n2K2

#2

6 + 6


3360 Simple Two-move Themes 1924
3310 2345 Chess Problems 1997
1355 The Guardian 2002

SOLUTION


  • SOUND
  • Sets
    • 1...Se2
      • 2.Sd3#
    • 1...Sb3
      • 2.Sd3#
    • 1...Sd3
      • 2.Sxd3#
    • 1...b4
      • 2.Qd5#
    • 1...f6
      • 2.Se6#
  • Tries
    • 1.Rh3?
      • 1...b4
        • 2.Qd5#
      • 1...Sc3
        • 2.Rxc3#
      • 1...Se2
        • 2.Sd3#
      • 1...Sb3
        • 2.Sd3#
      • 1...Sd3
        • 2.Sxd3#
      • 1...Sb4
        • 2.Rc3#
      • 1...f6
        • 2.Se6#
      • 1...h4!
  • Keys
    • 1.Qf3!
      • 1...Kb4
        • 2.Se6#
      • 1...Kc4
        • 2.Se6#
      • 1...Kd4
        • 2.Se6#
      • 1...Sc3
        • 2.Qxc3#
      • 1...Se2
        • 2.Sd3#
      • 1...Sb3
        • 2.Sd3#
      • 1...Sd3
        • 2.Sxd3#
      • 1...Sb4
        • 2.Qc3#
      • 1...b4
        • 2.Qd5#
      • 1...f6
        • 2.Se6#

There are these versions: 107890

FEATURES


  • Static
    • TYPE = INCOMPLETE_BLOCK
    • CHANGED MATES = 0
    • ADDED MATES = 5
    • REMOVED MATES = 0
  • Sets
    • S(a);N_GUARD::S(C)
    • S(a);N_GUARD::S(C),XS(a)
    • P(c);SBLOCK::QAR1(B)
    • P(f);N_GUARD::S(C)
  • Tries
    • Try
      • R(D);
      • Vars
        • P(c);SBLOCK::QAR1(B)
        • S(b);N_GUARD::R(D),XS(b)
        • S(a);N_GUARD::S(C)
        • S(a);N_GUARD::S(C),XS(a)
        • S(b);N_GUARD::R(D)
        • P(f);N_GUARD::S(C)
      • Refutation
        • P(e);
  • Actual
    • Q(B);
    • Vars
      • K(d);S_FLIGHT::R(D)+S(C)
      • K(d);P-FLIGHT::R(D)+S(C)
      • K(d);S_FLIGHT::R(D)+S(C),DCHECK
      • S(b);N_GUARD::QAR2(B),XS(b)
      • S(a);N_GUARD::S(C)
      • S(a);N_GUARD::S(C),XS(a)
      • S(b);N_GUARD::QAR2(B)
      • P(c);SBLOCK::QAR1(B)
      • P(f);N_GUARD::S(C)


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Implemented with HTML5, MySQL, Perl (with, inter alia, CGI::Simple, HTML::Template & XML::LibXML) & CSS/Javascript (jQuery, Bootstrap & DataTables).