Analysis of xx-top500-389-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: .3....41.8..5..9............9...1.......3..2.4.......82.68...........1.....2..... initial

Autosolve

position: .3592841.8215..9.3...1.3285392781654..84397214176523982.681.539.8.3..1.21.329.8.. autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* PRF # B9: 4,7 => SOL
* PRF # B3: 6 => SOL
* PRF # F8: 4,7 => SOL
* DIS # F9: 4,7 => CTR => F9: 5,6
* PRF # F2: 6 => SOL
* CNT   5 HDP CHAINS /  27 HYP OPENED

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

Pair Reduction

Pair Reduction

The following important HDP chains were detected:

* PRF # B9: 4,7 => SOL
* STA B9: 4,7
* CNT   1 HDP CHAINS /  13 HYP OPENED

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

Details

Positions

.3....41.8..5..9............9...1.......3..2.4.......82.68...........1.....2..... initial
.3592841.8215..9.3...1.3285392781654..84397214176523982.681.539.8.3..1.21.329.8.. autosolve
735928416821546973964173285392781654658439721417652398276814539589367142143295867 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (11)
A1: 6,7
C3: 4,9
E3: 6,7
I1: 6,7
H2: 6,7
A5: 5,6
B5: 5,6
B7: 4,7
C8: 4,9
F7: 4,7
I9: 6,7

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
B3,C3: 4.. / B3 = 4  => 10 pairs (_) / C3 = 4  => 11 pairs (_)
E2,F2: 4.. / E2 = 4  => 13 pairs (_) / F2 = 4  => 14 pairs (_)
H8,H9: 4.. / H8 = 4  => 16 pairs (_) / H9 = 4  => 13 pairs (_)
B7,F7: 4.. / B7 = 4  => 12 pairs (_) / F7 = 4  => 14 pairs (_)
C3,C8: 4.. / C3 = 4  => 11 pairs (_) / C8 = 4  => 10 pairs (_)
E2,E8: 4.. / E2 = 4  => 13 pairs (_) / E8 = 4  => 14 pairs (_)
A5,B5: 5.. / A5 = 5  => 11 pairs (_) / B5 = 5  =>  0 pairs (*)
A8,B9: 5.. / A8 = 5  =>  0 pairs (*) / B9 = 5  =>  0 pairs (X)
F8,F9: 5.. / F8 = 5  => 11 pairs (_) / F9 = 5  =>  0 pairs (*)
A8,F8: 5.. / A8 = 5  =>  0 pairs (*) / F8 = 5  =>  0 pairs (X)
B9,F9: 5.. / B9 = 5  => 11 pairs (_) / F9 = 5  =>  0 pairs (*)
A5,A8: 5.. / A5 = 5  => 11 pairs (_) / A8 = 5  =>  0 pairs (*)
B5,B9: 5.. / B5 = 5  =>  0 pairs (*) / B9 = 5  =>  0 pairs (X)
I1,H2: 6.. / I1 = 6  =>  0 pairs (*) / H2 = 6  =>  0 pairs (X)
A5,B5: 6.. / A5 = 6  =>  0 pairs (*) / B5 = 6  =>  0 pairs (X)
A1,I1: 6.. / A1 = 6  =>  0 pairs (X) / I1 = 6  =>  0 pairs (_)
B3,B5: 6.. / B3 = 6  =>  0 pairs (*) / B5 = 6  =>  0 pairs (X)
I1,I9: 6.. / I1 = 6  =>  0 pairs (*) / I9 = 6  =>  0 pairs (X)
I1,H2: 7.. / I1 = 7  =>  0 pairs (X) / H2 = 7  =>  0 pairs (_)
A1,I1: 7.. / A1 = 7  =>  0 pairs (*) / I1 = 7  =>  0 pairs (X)
B7,F7: 7.. / B7 = 7  => 14 pairs (_) / F7 = 7  => 12 pairs (_)
I1,I9: 7.. / I1 = 7  =>  0 pairs (X) / I9 = 7  =>  0 pairs (_)
A3,C3: 9.. / A3 = 9  => 11 pairs (_) / C3 = 9  => 10 pairs (_)
A8,C8: 9.. / A8 = 9  => 10 pairs (_) / C8 = 9  => 11 pairs (_)
A3,A8: 9.. / A3 = 9  => 11 pairs (_) / A8 = 9  => 10 pairs (_)
C3,C8: 9.. / C3 = 9  => 10 pairs (_) / C8 = 9  => 11 pairs (_)
* DURATION: 0:00:51.329731  START: 16:08:44.879694  END: 16:09:36.209425 2017-05-04
* CP COUNT: (26)
* SOLUTION FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A1,A5,B5,B7,C3,C8,E3,F7,H2,I1,I9)
* .3592841.8215..9.3...1.3285392781654..84397214176523982.681.539.8.3..1.21.329.8..
* PAIR A1: 6,7 BLK 1
A3: 6,7,9                                # reduction candidate for 6,7
A3: 6,7                                  # 10 pairs
B3: 6,7,4                                # reduction candidate for 6,7
B3: 6,7                                  # 11 pairs
* PAIR E3: 6,7 BLK 2
E2: 6,7,4                                # reduction candidate for 6,7
E2: 6,7                                  # 14 pairs
F2: 6,7,4                                # reduction candidate for 6,7
F2: 6,7                                  # 13 pairs
* PAIR E3: 6,7 ROW 3
A3: 6,7,9                                # reduction candidate for 6,7
A3: 6,7                                  # 10 pairs
B3: 6,7,4                                # reduction candidate for 6,7
B3: 6,7                                  # 11 pairs
* PAIR E3: 6,7 COL E
E8: 6,7,4                                # reduction candidate for 6,7
E8: 4                                    # 14 pairs
E8: 6,7                                  # 13 pairs
* PAIR H2: 6,7 ROW 2
E2: 6,7,4                                # reduction candidate for 6,7
E2: 6,7                                  # 14 pairs
F2: 6,7,4                                # reduction candidate for 6,7
F2: 6,7                                  # 13 pairs
* PAIR H2: 6,7 COL H
H8: 6,7,4                                # reduction candidate for 6,7
H8: 6,7                                  # 13 pairs
H9: 6,7,4                                # reduction candidate for 6,7
H9: 6,7                                  # 16 pairs
* PAIR B7: 4,7 BLK 7
B9: 4,7,5                                # reduction candidate for 4,7
B9: 4,7 => SOLVED
* 735928416821546973964173285392781654658439721417652398276814539589367142143295867
B9: 5                                    # 11 pairs
* PAIR B7: 4,7 COL B
B3: 4,7,6                                # reduction candidate for 4,7
B3: 6 => SOLVED
* 735928416821546973964173285392781654658439721417652398276814539589367142143295867
B3: 4,7                                  # 11 pairs
* PAIR F7: 4,7 BLK 8
E8: 4,7,6                                # reduction candidate for 4,7
E8: 4,7                                  # 15 pairs
F8: 4,7,5,6                              # reduction candidate for 4,7
F8: 4,7 => SOLVED
* 735928416821546973964173285392781654658439721417652398276814539589367142143295867
F8: 5,6                                  # 12 pairs
F9: 4,7,5,6                              # reduction candidate for 4,7
F9: 4,7 => CTR
* .3592841.8215.6973...1732853927816545684397214176523982768145399843651.215329.8..
F9: 5,6                                  # 12 pairs
* PAIR F7: 4,7 COL F
F2: 4,7,6                                # reduction candidate for 4,7
F2: 6 => SOLVED
* 735928416821546973964173285392781654658439721417652398276814539589367142143295867
F2: 4,7                                  # 15 pairs
* PAIR I9: 6,7 BLK 9
H8: 6,7,4                                # reduction candidate for 6,7
H8: 6,7                                  # 13 pairs
H9: 6,7,4                                # reduction candidate for 6,7
H9: 6,7                                  # 16 pairs
* PAIR I9: 6,7 ROW 9
F9: 6,7,4,5                              # reduction candidate for 6,7
F9: 6,7                                  # 13 pairs
F9: 4,5                                  # 13 pairs
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-389-base-pr-000.dot
* REASONING
* PRF # B9: 4,7 => SOL
* PRF # B3: 6 => SOL
* PRF # F8: 4,7 => SOL
* DIS # F9: 4,7 => CTR => F9: 5,6
* PRF # F2: 6 => SOL
* CNT   5 HDP CHAINS /  27 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A1,A5,B5,B7,C3,C8,E3,F7,H2,I1,I9)
* .3592841.8215..9.3...1.3285392781654..84397214176523982.681.539.8.3..1.21.329.8..
* PAIR A1: 6,7 BLK 1
A3: 6,7,9                                # reduction candidate for 6,7
A3: 6,7                                  # 10 pairs
B3: 6,7,4                                # reduction candidate for 6,7
B3: 6,7                                  # 11 pairs
* PAIR E3: 6,7 BLK 2
E2: 6,7,4                                # reduction candidate for 6,7
E2: 6,7                                  # 14 pairs
F2: 6,7,4                                # reduction candidate for 6,7
F2: 6,7                                  # 13 pairs
* PAIR E3: 6,7 ROW 3
A3: 6,7,9                                # reduction candidate for 6,7
A3: 6,7                                  # 10 pairs
B3: 6,7,4                                # reduction candidate for 6,7
B3: 6,7                                  # 11 pairs
* PAIR E3: 6,7 COL E
E8: 6,7,4                                # reduction candidate for 6,7
E8: 4                                    # 14 pairs
E8: 6,7                                  # 13 pairs
* PAIR H2: 6,7 ROW 2
E2: 6,7,4                                # reduction candidate for 6,7
E2: 6,7                                  # 14 pairs
F2: 6,7,4                                # reduction candidate for 6,7
F2: 6,7                                  # 13 pairs
* PAIR H2: 6,7 COL H
H8: 6,7,4                                # reduction candidate for 6,7
H8: 6,7                                  # 13 pairs
H9: 6,7,4                                # reduction candidate for 6,7
H9: 6,7                                  # 16 pairs
* PAIR B7: 4,7 BLK 7
B9: 4,7,5                                # reduction candidate for 4,7
B9: 4,7 => SOLVED
* 735928416821546973964173285392781654658439721417652398276814539589367142143295867
* DURATION: 0:00:15.709091  START: 16:10:08.580967  END: 16:10:24.290058 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-389-base-pr-001.dot
* REASONING
* PRF # B9: 4,7 => SOL
* STA B9: 4,7
* CNT   1 HDP CHAINS /  13 HYP OPENED

Header Info

Top 500 Minimum 17 389

solution: 735928416821546973964173285392781654658439721417652398276814539589367142143295867
info: 42012    FNBK     S8.f     48624

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

Solution

position: 735928416821546973964173285392781654658439721417652398276814539589367142143295867 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:

* INC # A3: 6,7 => UNS
* INC # B3: 6,7 => UNS
* INC # E2: 6,7 => UNS
* INC # F2: 6,7 => UNS
* INC # A3: 6,7 => UNS
* INC # B3: 6,7 => UNS
* INC # E8: 6,7 => UNS
* INC # E8: 4 => UNS
* INC # E2: 6,7 => UNS
* INC # F2: 6,7 => UNS
* INC # H8: 6,7 => UNS
* INC # H9: 6,7 => UNS
* PRF # B9: 4,7 => SOL
* INC # B9: 5 => UNS
* INC # B3: 4,7 => UNS
* PRF # B3: 6 => SOL
* INC # E8: 4,7 => UNS
* PRF # F8: 4,7 => SOL
* INC # F8: 5,6 => UNS
* DIS # F9: 4,7 => CTR => F9: 5,6
* INC # F9: 5,6 => UNS
* INC # F2: 4,7 => UNS
* PRF # F2: 6 => SOL
* INC # H8: 6,7 => UNS
* INC # H9: 6,7 => UNS
* INC # F9: 6,7 => UNS
* INC # F9: 4,5 => UNS
* CNT  27 HDP CHAINS /  27 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* INC # A3: 6,7 => UNS
* INC # B3: 6,7 => UNS
* INC # E2: 6,7 => UNS
* INC # F2: 6,7 => UNS
* INC # A3: 6,7 => UNS
* INC # B3: 6,7 => UNS
* INC # E8: 6,7 => UNS
* INC # E8: 4 => UNS
* INC # E2: 6,7 => UNS
* INC # F2: 6,7 => UNS
* INC # H8: 6,7 => UNS
* INC # H9: 6,7 => UNS
* PRF # B9: 4,7 => SOL
* STA B9: 4,7
* CNT  13 HDP CHAINS /  13 HYP OPENED