Analysis of xx-top500-204-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: ..7....5..1..8........4.3...4.2....13...5...........7.4..6..5.....7.1............ initial

Autosolve

position: .3791..5451438.7.....54731..45279.3137.154...1..8634754.16385.7.5.7.1.4.7..4.51.. autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* DIS # A1: 6,8 => CTR => A1: 2
* PRF # A1: 2 => SOL
* DIS # A3: 6,8 => CTR => A3: 2,9
* PRF # C3: 6,8 => SOL
* DIS # C3: 2,9 => CTR => C3: 6,8
* DIS # I3: 6,8 => CTR => I3: 2
* PRF # I3: 2 => SOL
* PRF # A1: 2,6 => SOL
* DIS # A1: 8 => CTR => A1: 2,6
* DIS # G1: 2,6 => CTR => G1: 8
* PRF # G1: 8 => SOL
* DIS # A1: 6,8 => CTR => A1: 2
* PRF # A1: 2 => SOL
* DIS # A3: 6,8 => CTR => A3: 2,9
* PRF # A8: 6,8 => SOL
* DIS # A8: 2,9 => CTR => A8: 6,8
* DIS # G5: 6,8 => CTR => G5: 2,9
* DIS # I5: 6,8 => CTR => I5: 2,9
* PRF # C3: 6,8 => SOL
* DIS # C3: 2,9 => CTR => C3: 6,8
* DIS # C8: 6,8 => CTR => C8: 2,3,9
* DIS # C9: 6,8 => CTR => C9: 2,3,9
* DIS # C3: 2,9 => CTR => C3: 6,8
* PRF # C3: 6,8 => SOL
* DIS # C8: 2,9 => CTR => C8: 3,6,8
* PRF # C9: 2,9 => SOL
* DIS # G5: 6,8 => CTR => G5: 2,9
* DIS # I5: 6,8 => CTR => I5: 2,9
* PRF # G1: 6,8 => SOL
* DIS # G1: 2 => CTR => G1: 6,8
* DIS # G8: 6,8 => CTR => G8: 2,9
* PRF # G8: 2,9 => SOL
* DIS # A8: 2,9 => CTR => A8: 6,8
* PRF # A8: 6,8 => SOL
* DIS # C8: 2,9 => CTR => C8: 3,6,8
* PRF # C9: 2,9 => SOL
* PRF # A8: 6,8 => SOL
* DIS # A8: 2,9 => CTR => A8: 6,8
* DIS # C8: 6,8 => CTR => C8: 2,3,9
* DIS # C9: 6,8 => CTR => C9: 2,3,9
* DIS # I9: 6,8 => CTR => I9: 2,3,9
* DIS # A8: 2,9 => CTR => A8: 6,8
* PRF # A8: 6,8 => SOL
* DIS # C8: 2,9 => CTR => C8: 3,6,8
* PRF # G8: 2,9 => SOL
* DIS # G8: 6,8 => CTR => G8: 2,9
* DIS # I8: 2,9 => CTR => I8: 3,6,8
* PRF # C9: 2,9 => SOL
* DIS # H9: 2,9 => CTR => H9: 6,8
* DIS # I9: 2,9 => CTR => I9: 3,6,8
* PRF # G8: 2,9 => SOL
* DIS # G8: 6,8 => CTR => G8: 2,9
* DIS # I8: 2,9 => CTR => I8: 3,6,8
* DIS # H9: 2,9 => CTR => H9: 6,8
* DIS # I9: 2,9 => CTR => I9: 3,6,8
* DIS # H5: 2,9 => CTR => H5: 6,8
* CNT  56 HDP CHAINS /  86 HYP OPENED

See Appendix: Full HDP Chains for full list of HDP chains.

Pair Reduction

Pair Reduction

The following important HDP chains were detected:

* DIS # A1: 6,8 => CTR => A1: 2
* PRF A1: 2 => SOL
* STA A1: 2
* CNT   2 HDP CHAINS /   1 HYP OPENED

See Appendix: Full HDP Chains for full list of HDP chains.

Details

Positions

..7....5..1..8........4.3...4.2....13...5...........7.4..6..5.....7.1............ initial
.3791..5451438.7.....54731..45279.3137.154...1..8634754.16385.7.5.7.1.4.7..4.51.. autosolve
237916854514382796968547312845279631376154289129863475491638527653721948782495163 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (13)
B3: 6,8
F1: 2,6
F2: 2,6
A4: 6,8
C5: 6,8
B6: 2,9
C6: 2,9
G4: 6,8
B7: 2,9
B9: 6,8
E8: 2,9
E9: 2,9
H7: 2,9

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
F1,F2: 2.. / F1 = 2  =>  0 pairs (X) / F2 = 2  => 16 pairs (_)
B6,C6: 2.. / B6 = 2  => 10 pairs (_) / C6 = 2  => 10 pairs (_)
E8,E9: 2.. / E8 = 2  => 11 pairs (_) / E9 = 2  => 11 pairs (_)
B7,H7: 2.. / B7 = 2  => 10 pairs (_) / H7 = 2  => 10 pairs (_)
B6,B7: 2.. / B6 = 2  => 10 pairs (_) / B7 = 2  => 10 pairs (_)
C8,C9: 3.. / C8 = 3  => 13 pairs (_) / C9 = 3  => 13 pairs (_)
I8,I9: 3.. / I8 = 3  => 13 pairs (_) / I9 = 3  => 13 pairs (_)
C8,I8: 3.. / C8 = 3  => 13 pairs (_) / I8 = 3  => 13 pairs (_)
C9,I9: 3.. / C9 = 3  => 13 pairs (_) / I9 = 3  => 13 pairs (_)
F1,F2: 6.. / F1 = 6  => 16 pairs (_) / F2 = 6  =>  0 pairs (X)
A4,C5: 6.. / A4 = 6  =>  0 pairs (X) / C5 = 6  =>  0 pairs (_)
A4,G4: 6.. / A4 = 6  =>  0 pairs (X) / G4 = 6  =>  0 pairs (_)
B3,B9: 6.. / B3 = 6  =>  0 pairs (*) / B9 = 6  =>  0 pairs (X)
G1,I3: 8.. / G1 = 8  =>  0 pairs (*) / I3 = 8  =>  0 pairs (X)
A4,C5: 8.. / A4 = 8  =>  0 pairs (*) / C5 = 8  =>  0 pairs (X)
A1,G1: 8.. / A1 = 8  =>  0 pairs (X) / G1 = 8  =>  0 pairs (_)
A4,G4: 8.. / A4 = 8  =>  0 pairs (*) / G4 = 8  =>  0 pairs (X)
B3,B9: 8.. / B3 = 8  =>  0 pairs (X) / B9 = 8  =>  0 pairs (_)
H5,H9: 8.. / H5 = 8  =>  0 pairs (*) / H9 = 8  =>  0 pairs (X)
A3,C3: 9.. / A3 = 9  => 13 pairs (_) / C3 = 9  =>  0 pairs (X)
H2,I2: 9.. / H2 = 9  => 16 pairs (_) / I2 = 9  => 14 pairs (_)
B6,C6: 9.. / B6 = 9  => 10 pairs (_) / C6 = 9  => 10 pairs (_)
E8,E9: 9.. / E8 = 9  => 11 pairs (_) / E9 = 9  => 11 pairs (_)
B7,H7: 9.. / B7 = 9  => 10 pairs (_) / H7 = 9  => 10 pairs (_)
A3,A8: 9.. / A3 = 9  => 13 pairs (_) / A8 = 9  =>  0 pairs (X)
B6,B7: 9.. / B6 = 9  => 10 pairs (_) / B7 = 9  => 10 pairs (_)
G5,G8: 9.. / G5 = 9  => 13 pairs (_) / G8 = 9  =>  0 pairs (*)
* DURATION: 0:00:46.019564  START: 09:46:16.736375  END: 09:47:02.755939 2017-05-04
* CP COUNT: (27)
* SOLUTION FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A4,B3,B6,B7,B9,C5,C6,E8,E9,F1,F2,G4,H7)
* .3791..5451438.7.....54731..45279.3137.154...1..8634754.16385.7.5.7.1.4.7..4.51..
* PAIR B3: 6,8 BLK 1
A1: 6,8,2                                # reduction candidate for 6,8
A1: 6,8 => CTR
* 8379162545143827...6.5473186452798313781549..1..8634754.16385.7.5.7.16437..4.51..
A1: 2 => SOLVED
* 237916854514382796968547312845279631376154289129863475491638527653721948782495163
A3: 6,8,2,9                              # reduction candidate for 6,8
A3: 6,8 => CTR
* .3791..5451438.7....9547312.45279.3137.154...19286347542163859795.721.4.7..49512.
A3: 2,9                                  # 14 pairs
C3: 6,8,2,9                              # reduction candidate for 6,8
C3: 6,8 => SOLVED
* 237916854514382796968547312845279631376154289129863475491638527653721948782495163
C3: 2,9 => CTR
* 8379162545143827...6.5473186452798313781549..1..8634754.16385.7.5.7.16437..4.51..
* PAIR B3: 6,8 ROW 3
I3: 6,8,2                                # reduction candidate for 6,8
I3: 6,8 => CTR
* 8379162545143827...6.5473186452798313781549..1..8634754.16385.7.5.7.16437..4.51..
I3: 2 => SOLVED
* 237916854514382796968547312845279631376154289129863475491638527653721948782495163
* PAIR F1: 2,6 ROW 1
A1: 2,6,8                                # reduction candidate for 2,6
A1: 2,6 => SOLVED
* 237916854514382796968547312845279631376154289129863475491638527653721948782495163
A1: 8 => CTR
* 83791..5451438.7...6.547318645279831378154...1..8634754.16385.7.5.7.1.4.78.4.51..
G1: 2,6,8                                # reduction candidate for 2,6
G1: 2,6 => CTR
* 83791..5451438.7...6.547318645279831378154...1..8634754.16385.7.5.7.1.4.78.4.51..
G1: 8 => SOLVED
* 237916854514382796968547312845279631376154289129863475491638527653721948782495163
* PAIR F2: 2,6 ROW 2
H2: 2,6,9                                # reduction candidate for 2,6
H2: 2,6                                  # 14 pairs
I2: 2,6,9                                # reduction candidate for 2,6
I2: 2,6                                  # 16 pairs
* PAIR A4: 6,8 COL A
A1: 6,8,2                                # reduction candidate for 6,8
A1: 6,8 => CTR
* 8379162545143827...6.5473186452798313781549..1..8634754.16385.7.5.7.16437..4.51..
A1: 2 => SOLVED
* 237916854514382796968547312845279631376154289129863475491638527653721948782495163
A3: 6,8,2,9                              # reduction candidate for 6,8
A3: 6,8 => CTR
* .3791..5451438.7....9547312.45279.3137.154...19286347542163859795.721.4.7..49512.
A3: 2,9                                  # 14 pairs
A8: 6,8,2,9                              # reduction candidate for 6,8
A8: 6,8 => SOLVED
* 237916854514382796968547312845279631376154289129863475491638527653721948782495163
A8: 2,9 => CTR
* 8379162545143827...6.5473186452798313781549..1..8634754.16385.7.5.7.16437..4.51..
* PAIR C5: 6,8 ROW 5
G5: 6,8,2,9                              # reduction candidate for 6,8
G5: 6,8 => CTR
* .3791.2545143827..9.2547318.45279.3137.154...12986347549163852725.7.194.7..4951..
G5: 2,9                                  # 14 pairs
H5: 6,8,2,9                              # reduction candidate for 6,8
H5: 6,8                                  # 16 pairs
I5: 6,8,2,9                              # reduction candidate for 6,8
I5: 6,8 => CTR
* .37916.54514382769.8.547312.45279.3137.154..81..8634754.16385.7.587.1.4376.4.518.
I5: 2,9                                  # 14 pairs
* PAIR C5: 6,8 COL C
C3: 6,8,2,9                              # reduction candidate for 6,8
C3: 6,8 => SOLVED
* 237916854514382796968547312845279631376154289129863475491638527653721948782495163
C3: 2,9 => CTR
* 8379162545143827...6.5473186452798313781549..1..8634754.16385.7.5.7.16437..4.51..
C8: 6,8,2,3,9                            # reduction candidate for 6,8
C8: 6,8 => CTR
* 8379162545143827...6.547318645279831378154...1..8634754.16385.7.5.7.1.437.34.51..
C8: 2,3,9                                # 13 pairs
C9: 6,8,2,3,9                            # reduction candidate for 6,8
C9: 6,8 => CTR
* 837916254514382769.6.54731864527983137.154...1..8634754.16385.7.537.1.4.7..4.51.3
C9: 2,3,9                                # 13 pairs
* PAIR C6: 2,9 COL C
C3: 2,9,6,8                              # reduction candidate for 2,9
C3: 2,9 => CTR
* 8379162545143827...6.5473186452798313781549..1..8634754.16385.7.5.7.16437..4.51..
C3: 6,8 => SOLVED
* 237916854514382796968547312845279631376154289129863475491638527653721948782495163
C8: 2,9,3,6,8                            # reduction candidate for 2,9
C8: 2,9 => CTR
* .3791..5451438.7.....54731..45279.3137.154...1..8634754.16385.7.5.7.1.437.34.51..
C8: 3,6,8                                # 13 pairs
C9: 2,9,3,6,8                            # reduction candidate for 2,9
C9: 2,9 => SOLVED
* 237916854514382796968547312845279631376154289129863475491638527653721948782495163
C9: 3,6,8                                # 13 pairs
* PAIR G4: 6,8 BLK 6
G5: 6,8,2,9                              # reduction candidate for 6,8
G5: 6,8 => CTR
* .3791.2545143827..9.2547318.45279.3137.154...12986347549163852725.7.194.7..4951..
G5: 2,9                                  # 14 pairs
H5: 6,8,2,9                              # reduction candidate for 6,8
H5: 6,8                                  # 16 pairs
I5: 6,8,2,9                              # reduction candidate for 6,8
I5: 6,8 => CTR
* .37916.54514382769.8.547312.45279.3137.154..81..8634754.16385.7.587.1.4376.4.518.
I5: 2,9                                  # 14 pairs
* PAIR G4: 6,8 COL G
G1: 6,8,2                                # reduction candidate for 6,8
G1: 6,8 => SOLVED
* 237916854514382796968547312845279631376154289129863475491638527653721948782495163
G1: 2 => CTR
* 8379162545143827...6.547318645279831378154...1..8634754.16385.7.5.7.1.4.78.4.51..
G8: 6,8,2,9                              # reduction candidate for 6,8
G8: 6,8 => CTR
* 8379162545143827...6.54731864527983137.1549..1..8634754.16385.7.5.7.1.4.78.4.51..
G8: 2,9 => SOLVED
* 237916854514382796968547312845279631376154289129863475491638527653721948782495163
* PAIR B7: 2,9 BLK 7
A8: 2,9,6,8                              # reduction candidate for 2,9
A8: 2,9 => CTR
* 8379162545143827...6.5473186452798313781549..1..8634754.16385.7.5.7.16437..4.51..
A8: 6,8 => SOLVED
* 237916854514382796968547312845279631376154289129863475491638527653721948782495163
C8: 2,9,3,6,8                            # reduction candidate for 2,9
C8: 2,9 => CTR
* .3791..5451438.7.....54731..45279.3137.154...1..8634754.16385.7.5.7.1.437.34.51..
C8: 3,6,8                                # 13 pairs
C9: 2,9,3,6,8                            # reduction candidate for 2,9
C9: 2,9 => SOLVED
* 237916854514382796968547312845279631376154289129863475491638527653721948782495163
C9: 3,6,8                                # 13 pairs
* PAIR B9: 6,8 BLK 7
A8: 6,8,2,9                              # reduction candidate for 6,8
A8: 6,8 => SOLVED
* 237916854514382796968547312845279631376154289129863475491638527653721948782495163
A8: 2,9 => CTR
* 8379162545143827...6.5473186452798313781549..1..8634754.16385.7.5.7.16437..4.51..
C8: 6,8,2,3,9                            # reduction candidate for 6,8
C8: 6,8 => CTR
* 8379162545143827...6.547318645279831378154...1..8634754.16385.7.5.7.1.437.34.51..
C8: 2,3,9                                # 13 pairs
C9: 6,8,2,3,9                            # reduction candidate for 6,8
C9: 6,8 => CTR
* 837916254514382769.6.54731864527983137.154...1..8634754.16385.7.537.1.4.7..4.51.3
C9: 2,3,9                                # 13 pairs
* PAIR B9: 6,8 ROW 9
H9: 6,8,2,9                              # reduction candidate for 6,8
H9: 6,8                                  # 14 pairs
I9: 6,8,2,3,9                            # reduction candidate for 6,8
I9: 6,8 => CTR
* .37916254514382769.6.547318845279.3137.1549821..8634754.16385.7.5.7.1.437.34.51.6
I9: 2,3,9                                # 13 pairs
* PAIR E8: 2,9 ROW 8
A8: 2,9,6,8                              # reduction candidate for 2,9
A8: 2,9 => CTR
* 8379162545143827...6.5473186452798313781549..1..8634754.16385.7.5.7.16437..4.51..
A8: 6,8 => SOLVED
* 237916854514382796968547312845279631376154289129863475491638527653721948782495163
C8: 2,9,3,6,8                            # reduction candidate for 2,9
C8: 2,9 => CTR
* .3791..5451438.7.....54731..45279.3137.154...1..8634754.16385.7.5.7.1.437.34.51..
C8: 3,6,8                                # 13 pairs
G8: 2,9,6,8                              # reduction candidate for 2,9
G8: 2,9 => SOLVED
* 237916854514382796968547312845279631376154289129863475491638527653721948782495163
G8: 6,8 => CTR
* 8379162545143827...6.54731864527983137.1549..1..8634754.16385.7.5.7.1.4.78.4.51..
I8: 2,9,3,6,8                            # reduction candidate for 2,9
I8: 2,9 => CTR
* .3791..5451438.7.....54731..45279.3137.154...1..8634754.16385.7.537.1.4.7..4.51.3
I8: 3,6,8                                # 13 pairs
* PAIR E9: 2,9 ROW 9
C9: 2,9,3,6,8                            # reduction candidate for 2,9
C9: 2,9 => SOLVED
* 237916854514382796968547312845279631376154289129863475491638527653721948782495163
C9: 3,6,8                                # 13 pairs
H9: 2,9,6,8                              # reduction candidate for 2,9
H9: 2,9 => CTR
* .3791..5451438.769...54731.8452796313761549821..8634754.16385.7.5.7.1.4.7..4.51..
H9: 6,8                                  # 14 pairs
I9: 2,9,3,6,8                            # reduction candidate for 2,9
I9: 2,9 => CTR
* 8379162545143827...6.547318645279831378154...1..8634754.16385.7.5.7.1.437.34.51..
I9: 3,6,8                                # 13 pairs
* PAIR H7: 2,9 BLK 9
G8: 2,9,6,8                              # reduction candidate for 2,9
G8: 2,9 => SOLVED
* 237916854514382796968547312845279631376154289129863475491638527653721948782495163
G8: 6,8 => CTR
* 8379162545143827...6.54731864527983137.1549..1..8634754.16385.7.5.7.1.4.78.4.51..
I8: 2,9,3,6,8                            # reduction candidate for 2,9
I8: 2,9 => CTR
* .3791..5451438.7.....54731..45279.3137.154...1..8634754.16385.7.537.1.4.7..4.51.3
I8: 3,6,8                                # 13 pairs
H9: 2,9,6,8                              # reduction candidate for 2,9
H9: 2,9 => CTR
* .3791..5451438.769...54731.8452796313761549821..8634754.16385.7.5.7.1.4.7..4.51..
H9: 6,8                                  # 14 pairs
I9: 2,9,3,6,8                            # reduction candidate for 2,9
I9: 2,9 => CTR
* 8379162545143827...6.547318645279831378154...1..8634754.16385.7.5.7.1.437.34.51..
I9: 3,6,8                                # 13 pairs
* PAIR H7: 2,9 COL H
H2: 2,9,6                                # reduction candidate for 2,9
H2: 2,9                                  # 18 pairs
H5: 2,9,6,8                              # reduction candidate for 2,9
H5: 2,9 => CTR
* .3791..5451438.769.8.547312.45279.3137.154..81..8634754.16385.7.587.1.4376.4.518.
H5: 6,8                                  # 16 pairs
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-204-base-pr-000.dot
* REASONING
* DIS # A1: 6,8 => CTR => A1: 2
* PRF # A1: 2 => SOL
* DIS # A3: 6,8 => CTR => A3: 2,9
* PRF # C3: 6,8 => SOL
* DIS # C3: 2,9 => CTR => C3: 6,8
* DIS # I3: 6,8 => CTR => I3: 2
* PRF # I3: 2 => SOL
* PRF # A1: 2,6 => SOL
* DIS # A1: 8 => CTR => A1: 2,6
* DIS # G1: 2,6 => CTR => G1: 8
* PRF # G1: 8 => SOL
* DIS # A1: 6,8 => CTR => A1: 2
* PRF # A1: 2 => SOL
* DIS # A3: 6,8 => CTR => A3: 2,9
* PRF # A8: 6,8 => SOL
* DIS # A8: 2,9 => CTR => A8: 6,8
* DIS # G5: 6,8 => CTR => G5: 2,9
* DIS # I5: 6,8 => CTR => I5: 2,9
* PRF # C3: 6,8 => SOL
* DIS # C3: 2,9 => CTR => C3: 6,8
* DIS # C8: 6,8 => CTR => C8: 2,3,9
* DIS # C9: 6,8 => CTR => C9: 2,3,9
* DIS # C3: 2,9 => CTR => C3: 6,8
* PRF # C3: 6,8 => SOL
* DIS # C8: 2,9 => CTR => C8: 3,6,8
* PRF # C9: 2,9 => SOL
* DIS # G5: 6,8 => CTR => G5: 2,9
* DIS # I5: 6,8 => CTR => I5: 2,9
* PRF # G1: 6,8 => SOL
* DIS # G1: 2 => CTR => G1: 6,8
* DIS # G8: 6,8 => CTR => G8: 2,9
* PRF # G8: 2,9 => SOL
* DIS # A8: 2,9 => CTR => A8: 6,8
* PRF # A8: 6,8 => SOL
* DIS # C8: 2,9 => CTR => C8: 3,6,8
* PRF # C9: 2,9 => SOL
* PRF # A8: 6,8 => SOL
* DIS # A8: 2,9 => CTR => A8: 6,8
* DIS # C8: 6,8 => CTR => C8: 2,3,9
* DIS # C9: 6,8 => CTR => C9: 2,3,9
* DIS # I9: 6,8 => CTR => I9: 2,3,9
* DIS # A8: 2,9 => CTR => A8: 6,8
* PRF # A8: 6,8 => SOL
* DIS # C8: 2,9 => CTR => C8: 3,6,8
* PRF # G8: 2,9 => SOL
* DIS # G8: 6,8 => CTR => G8: 2,9
* DIS # I8: 2,9 => CTR => I8: 3,6,8
* PRF # C9: 2,9 => SOL
* DIS # H9: 2,9 => CTR => H9: 6,8
* DIS # I9: 2,9 => CTR => I9: 3,6,8
* PRF # G8: 2,9 => SOL
* DIS # G8: 6,8 => CTR => G8: 2,9
* DIS # I8: 2,9 => CTR => I8: 3,6,8
* DIS # H9: 2,9 => CTR => H9: 6,8
* DIS # I9: 2,9 => CTR => I9: 3,6,8
* DIS # H5: 2,9 => CTR => H5: 6,8
* CNT  56 HDP CHAINS /  86 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A4,B3,B6,B7,B9,C5,C6,E8,E9,F1,F2,G4,H7)
* .3791..5451438.7.....54731..45279.3137.154...1..8634754.16385.7.5.7.1.4.7..4.51..
* PAIR B3: 6,8 BLK 1
A1: 6,8,2                                # reduction candidate for 6,8
A1: 6,8 => CTR
* 8379162545143827...6.5473186452798313781549..1..8634754.16385.7.5.7.16437..4.51..
A1: 2 => SOLVED
* 237916854514382796968547312845279631376154289129863475491638527653721948782495163
* DURATION: 0:00:01.784586  START: 09:48:27.841811  END: 09:48:29.626397 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-204-base-pr-001.dot
* REASONING
* DIS # A1: 6,8 => CTR => A1: 2
* PRF A1: 2 => SOL
* STA A1: 2
* CNT   2 HDP CHAINS /   1 HYP OPENED

Header Info

Top 500 Minimum 17 204

solution: 237916854514382796968547312845279631376154289129863475491638527653721948782495163
info: 1893     FNBTHWX  S8.f     42690

http://www.sfsudoku.com/su17ExtremeDiff500.txt from http://www.minimumsudoku.com/

Solution

position: 237916854514382796968547312845279631376154289129863475491638527653721948782495163 solved
Solution

See section Pair Reduction for the HDP chains leading to this result.

Appendix: Full HDP Chains

A1. Pair Reduction Analysis

Full list of HDP chains traversed:

* DIS # A1: 6,8 => CTR => A1: 2
* PRF # A1: 2 => SOL
* DIS # A3: 6,8 => CTR => A3: 2,9
* INC # A3: 2,9 => UNS
* PRF # C3: 6,8 => SOL
* DIS # C3: 2,9 => CTR => C3: 6,8
* DIS # I3: 6,8 => CTR => I3: 2
* PRF # I3: 2 => SOL
* PRF # A1: 2,6 => SOL
* DIS # A1: 8 => CTR => A1: 2,6
* DIS # G1: 2,6 => CTR => G1: 8
* PRF # G1: 8 => SOL
* INC # H2: 2,6 => UNS
* INC # I2: 2,6 => UNS
* DIS # A1: 6,8 => CTR => A1: 2
* PRF # A1: 2 => SOL
* DIS # A3: 6,8 => CTR => A3: 2,9
* INC # A3: 2,9 => UNS
* PRF # A8: 6,8 => SOL
* DIS # A8: 2,9 => CTR => A8: 6,8
* DIS # G5: 6,8 => CTR => G5: 2,9
* INC # G5: 2,9 => UNS
* INC # H5: 6,8 => UNS
* DIS # I5: 6,8 => CTR => I5: 2,9
* INC # I5: 2,9 => UNS
* PRF # C3: 6,8 => SOL
* DIS # C3: 2,9 => CTR => C3: 6,8
* DIS # C8: 6,8 => CTR => C8: 2,3,9
* INC # C8: 2,3,9 => UNS
* DIS # C9: 6,8 => CTR => C9: 2,3,9
* INC # C9: 2,3,9 => UNS
* DIS # C3: 2,9 => CTR => C3: 6,8
* PRF # C3: 6,8 => SOL
* DIS # C8: 2,9 => CTR => C8: 3,6,8
* INC # C8: 3,6,8 => UNS
* PRF # C9: 2,9 => SOL
* INC # C9: 3,6,8 => UNS
* DIS # G5: 6,8 => CTR => G5: 2,9
* INC # G5: 2,9 => UNS
* INC # H5: 6,8 => UNS
* DIS # I5: 6,8 => CTR => I5: 2,9
* INC # I5: 2,9 => UNS
* PRF # G1: 6,8 => SOL
* DIS # G1: 2 => CTR => G1: 6,8
* DIS # G8: 6,8 => CTR => G8: 2,9
* PRF # G8: 2,9 => SOL
* DIS # A8: 2,9 => CTR => A8: 6,8
* PRF # A8: 6,8 => SOL
* DIS # C8: 2,9 => CTR => C8: 3,6,8
* INC # C8: 3,6,8 => UNS
* PRF # C9: 2,9 => SOL
* INC # C9: 3,6,8 => UNS
* PRF # A8: 6,8 => SOL
* DIS # A8: 2,9 => CTR => A8: 6,8
* DIS # C8: 6,8 => CTR => C8: 2,3,9
* INC # C8: 2,3,9 => UNS
* DIS # C9: 6,8 => CTR => C9: 2,3,9
* INC # C9: 2,3,9 => UNS
* INC # H9: 6,8 => UNS
* DIS # I9: 6,8 => CTR => I9: 2,3,9
* INC # I9: 2,3,9 => UNS
* DIS # A8: 2,9 => CTR => A8: 6,8
* PRF # A8: 6,8 => SOL
* DIS # C8: 2,9 => CTR => C8: 3,6,8
* INC # C8: 3,6,8 => UNS
* PRF # G8: 2,9 => SOL
* DIS # G8: 6,8 => CTR => G8: 2,9
* DIS # I8: 2,9 => CTR => I8: 3,6,8
* INC # I8: 3,6,8 => UNS
* PRF # C9: 2,9 => SOL
* INC # C9: 3,6,8 => UNS
* DIS # H9: 2,9 => CTR => H9: 6,8
* INC # H9: 6,8 => UNS
* DIS # I9: 2,9 => CTR => I9: 3,6,8
* INC # I9: 3,6,8 => UNS
* PRF # G8: 2,9 => SOL
* DIS # G8: 6,8 => CTR => G8: 2,9
* DIS # I8: 2,9 => CTR => I8: 3,6,8
* INC # I8: 3,6,8 => UNS
* DIS # H9: 2,9 => CTR => H9: 6,8
* INC # H9: 6,8 => UNS
* DIS # I9: 2,9 => CTR => I9: 3,6,8
* INC # I9: 3,6,8 => UNS
* INC # H2: 2,9 => UNS
* DIS # H5: 2,9 => CTR => H5: 6,8
* INC # H5: 6,8 => UNS
* CNT  86 HDP CHAINS /  86 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* DIS # A1: 6,8 => CTR => A1: 2
* PRF A1: 2 => SOL
* STA A1: 2
* CNT   2 HDP CHAINS /   1 HYP OPENED