Analysis of xx-top500-229-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: ...6....12......4.....5......67..5...1.....2....3.....8...24...4.....6........3.. initial

Autosolve

position: .3864.2512518...466.4251.3..467.251..1.4...2..8231.46.8639241754.51..6.212.5..3.4 autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* DIS # A5: 7,9 => CTR => A5: 3,5
* DIS # A5: 3,9 => CTR => A5: 5,7
* DIS # A5: 7,9 => CTR => A5: 3,5
* DIS # I5: 7,9 => CTR => I5: 3,8
* DIS # I4: 3 => CTR => I4: 8,9
* DIS # F5: 5,9 => CTR => F5: 6,8
* DIS # A6: 7 => CTR => A6: 5,9
* DIS # I5: 7,9 => CTR => I5: 3,8
* DIS # A6: 5 => CTR => A6: 7,9
* CNT   9 HDP CHAINS /  38 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 # A5: 7,9 => CTR => A5: 3,5
* DIS A5: 3,5 # A6: 5 => CTR => A6: 7,9
* PRF A5: 3,5 + A6: 7,9 # G3: 7,9 => SOL
* STA A5: 3,5 + A6: 7,9 + G3: 7,9
* CNT   3 HDP CHAINS /   5 HYP OPENED

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

Details

Positions

...6....12......4.....5......67..5...1.....2....3.....8...24...4.....6........3.. initial
.3864.2512518...466.4251.3..467.251..1.4...2..8231.46.8639241754.51..6.212.5..3.4 autosolve
738649251251873946694251738346782519517496823982315467863924175475138692129567384 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (13)
A1: 7,9
B3: 7,9
F1: 7,9
G2: 7,9
A4: 3,9
C5: 7,9
E4: 8,9
F6: 5,9
I6: 7,9
B8: 7,9
C9: 7,9
H8: 8,9
H9: 8,9

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
E2,F2: 3.. / E2 = 3  => 17 pairs (_) / F2 = 3  => 15 pairs (_)
A4,A5: 3.. / A4 = 3  => 13 pairs (_) / A5 = 3  =>  0 pairs (X)
I4,I5: 3.. / I4 = 3  =>  0 pairs (X) / I5 = 3  => 13 pairs (_)
E8,F8: 3.. / E8 = 3  => 15 pairs (_) / F8 = 3  => 17 pairs (_)
A4,I4: 3.. / A4 = 3  => 13 pairs (_) / I4 = 3  =>  0 pairs (X)
A5,I5: 3.. / A5 = 3  =>  0 pairs (X) / I5 = 3  => 13 pairs (_)
E2,E8: 3.. / E2 = 3  => 17 pairs (_) / E8 = 3  => 15 pairs (_)
F2,F8: 3.. / F2 = 3  => 15 pairs (_) / F8 = 3  => 17 pairs (_)
A5,A6: 5.. / A5 = 5  => 13 pairs (_) / A6 = 5  =>  0 pairs (X)
F5,F6: 5.. / F5 = 5  =>  0 pairs (X) / F6 = 5  => 13 pairs (_)
A5,F5: 5.. / A5 = 5  => 13 pairs (_) / F5 = 5  =>  0 pairs (X)
A6,F6: 5.. / A6 = 5  =>  0 pairs (X) / F6 = 5  => 13 pairs (_)
E5,F5: 6.. / E5 = 6  => 14 pairs (_) / F5 = 6  => 17 pairs (_)
E9,F9: 6.. / E9 = 6  => 17 pairs (_) / F9 = 6  => 14 pairs (_)
E5,E9: 6.. / E5 = 6  => 14 pairs (_) / E9 = 6  => 17 pairs (_)
F5,F9: 6.. / F5 = 6  => 17 pairs (_) / F9 = 6  => 14 pairs (_)
A1,B3: 7.. / A1 = 7  =>  0 pairs (*) / B3 = 7  =>  0 pairs (X)
B8,C9: 7.. / B8 = 7  =>  0 pairs (*) / C9 = 7  =>  0 pairs (X)
A1,F1: 7.. / A1 = 7  =>  0 pairs (*) / F1 = 7  =>  0 pairs (X)
A6,I6: 7.. / A6 = 7  =>  0 pairs (X) / I6 = 7  => 15 pairs (_)
B3,B8: 7.. / B3 = 7  =>  0 pairs (X) / B8 = 7  =>  0 pairs (_)
C5,C9: 7.. / C5 = 7  =>  0 pairs (*) / C9 = 7  =>  0 pairs (X)
G3,I3: 8.. / G3 = 8  => 19 pairs (_) / I3 = 8  => 17 pairs (_)
H8,H9: 8.. / H8 = 8  =>  0 pairs (X) / H9 = 8  =>  0 pairs (_)
E4,I4: 8.. / E4 = 8  => 16 pairs (_) / I4 = 8  => 16 pairs (_)
G3,G5: 8.. / G3 = 8  => 19 pairs (_) / G5 = 8  => 17 pairs (_)
A1,B3: 9.. / A1 = 9  =>  0 pairs (X) / B3 = 9  =>  0 pairs (_)
B8,C9: 9.. / B8 = 9  =>  0 pairs (X) / C9 = 9  =>  0 pairs (_)
H8,H9: 9.. / H8 = 9  =>  0 pairs (*) / H9 = 9  =>  0 pairs (X)
A1,F1: 9.. / A1 = 9  =>  0 pairs (X) / F1 = 9  =>  0 pairs (_)
B8,H8: 9.. / B8 = 9  =>  0 pairs (X) / H8 = 9  =>  0 pairs (_)
C9,H9: 9.. / C9 = 9  =>  0 pairs (*) / H9 = 9  =>  0 pairs (X)
B3,B8: 9.. / B3 = 9  =>  0 pairs (*) / B8 = 9  =>  0 pairs (X)
C5,C9: 9.. / C5 = 9  =>  0 pairs (X) / C9 = 9  =>  0 pairs (_)
* DURATION: 0:00:55.674381  START: 10:40:15.139462  END: 10:41:10.813843 2017-05-04
* CP COUNT: (34)
* SOLUTION FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A1,A4,B3,B8,C5,C9,E4,F1,F6,G2,H8,H9,I6)
* .3864.2512518...466.4251.3..467.251..1.4...2..8231.46.8639241754.51..6.212.5..3.4
* PAIR A1: 7,9 COL A
A5: 7,9,3,5                              # reduction candidate for 7,9
A5: 7,9 => CTR
* 938647251251893746674251.3.34678251..1.4.5.235823194678639241754.51..6.212.5.63.4
A5: 3,5                                  # 14 pairs
A6: 7,9,5                                # reduction candidate for 7,9
A6: 7,9                                  # 13 pairs
* PAIR B3: 7,9 ROW 3
G3: 7,9,8                                # reduction candidate for 7,9
G3: 7,9                                  # 17 pairs
I3: 7,9,8                                # reduction candidate for 7,9
I3: 7,9                                  # 19 pairs
* PAIR F1: 7,9 BLK 2
E2: 7,9,3                                # reduction candidate for 7,9
E2: 7,9                                  # 15 pairs
F2: 7,9,3                                # reduction candidate for 7,9
F2: 7,9                                  # 17 pairs
* PAIR G2: 7,9 BLK 3
G3: 7,9,8                                # reduction candidate for 7,9
G3: 7,9                                  # 17 pairs
I3: 7,9,8                                # reduction candidate for 7,9
I3: 7,9                                  # 19 pairs
* PAIR G2: 7,9 ROW 2
E2: 7,9,3                                # reduction candidate for 7,9
E2: 7,9                                  # 15 pairs
F2: 7,9,3                                # reduction candidate for 7,9
F2: 7,9                                  # 17 pairs
* PAIR G2: 7,9 COL G
G5: 7,9,8                                # reduction candidate for 7,9
G5: 7,9                                  # 19 pairs
G5: 8                                    # 17 pairs
* PAIR A4: 3,9 BLK 4
A5: 3,9,5,7                              # reduction candidate for 3,9
A5: 3,9 => CTR
* .3864.2512518...466.4251.3..467.251..1.4.5.2.5823194678639241754.51..6.212.5.63.4
A5: 5,7                                  # 14 pairs
* PAIR A4: 3,9 ROW 4
I4: 3,9,8                                # reduction candidate for 3,9
I4: 8                                    # 16 pairs
I4: 3,9                                  # 16 pairs
* PAIR C5: 7,9 BLK 4
A5: 7,9,3,5                              # reduction candidate for 7,9
A5: 7,9 => CTR
* 938647251251893746674251.3.34678251..1.4.5.235823194678639241754.51..6.212.5.63.4
A5: 3,5                                  # 14 pairs
A6: 7,9,5                                # reduction candidate for 7,9
A6: 7,9                                  # 13 pairs
* PAIR C5: 7,9 ROW 5
G5: 7,9,8                                # reduction candidate for 7,9
G5: 7,9                                  # 19 pairs
I5: 7,9,3,8                              # reduction candidate for 7,9
I5: 7,9 => CTR
* .3864.2512518...466.4251.3..467.251331.4.582.5823194678639241754.51..6.212.5.63.4
I5: 3,8                                  # 14 pairs
* PAIR E4: 8,9 BLK 5
E5: 8,9,6                                # reduction candidate for 8,9
E5: 8,9                                  # 17 pairs
F5: 8,9,5,6                              # reduction candidate for 8,9
F5: 8,9                                  # 15 pairs
* PAIR E4: 8,9 ROW 4
I4: 8,9,3                                # reduction candidate for 8,9
I4: 3 => CTR
* .3864.2512518...466.4251.3..4678251331.4.5.2.5823194678639241754.51..6.212.5.6384
I4: 8,9                                  # 13 pairs
* PAIR F6: 5,9 BLK 5
F5: 5,9,6,8                              # reduction candidate for 5,9
F5: 5,9 => CTR
* .3864.2512518937466.4251.3..4678251..1.46..2..8231.46.8639241754.51.8692129576384
F5: 6,8                                  # 15 pairs
* PAIR F6: 5,9 ROW 6
A6: 5,9,7                                # reduction candidate for 5,9
A6: 7 => CTR
* 9386472512518..746674251938.467.251.51.4...237823154698639241754.51..6.21275..394
A6: 5,9                                  # 15 pairs
* PAIR I6: 7,9 BLK 6
G5: 7,9,8                                # reduction candidate for 7,9
G5: 7,9                                  # 19 pairs
I5: 7,9,3,8                              # reduction candidate for 7,9
I5: 7,9 => CTR
* .3864.2512518...466.4251.3..467.251331.4.582.5823194678639241754.51..6.212.5.63.4
I5: 3,8                                  # 14 pairs
* PAIR I6: 7,9 ROW 6
A6: 7,9,5                                # reduction candidate for 7,9
A6: 5 => CTR
* 938647251251893746674251.3.34678251..1.4...2.5823194678639241754.51..6.212.5..3.4
A6: 7,9                                  # 13 pairs
* PAIR I6: 7,9 COL I
I3: 7,9,8                                # reduction candidate for 7,9
I3: 7,9                                  # 19 pairs
I3: 8                                    # 17 pairs
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-229-base-pr-000.dot
* REASONING
* DIS # A5: 7,9 => CTR => A5: 3,5
* DIS # A5: 3,9 => CTR => A5: 5,7
* DIS # A5: 7,9 => CTR => A5: 3,5
* DIS # I5: 7,9 => CTR => I5: 3,8
* DIS # I4: 3 => CTR => I4: 8,9
* DIS # F5: 5,9 => CTR => F5: 6,8
* DIS # A6: 7 => CTR => A6: 5,9
* DIS # I5: 7,9 => CTR => I5: 3,8
* DIS # A6: 5 => CTR => A6: 7,9
* CNT   9 HDP CHAINS /  38 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A1,A4,B3,B8,C5,C9,E4,F1,F6,G2,H8,H9,I6)
* .3864.2512518...466.4251.3..467.251..1.4...2..8231.46.8639241754.51..6.212.5..3.4
* PAIR A1: 7,9 COL A
A5: 7,9,3,5                              # reduction candidate for 7,9
A5: 7,9 => CTR
* 938647251251893746674251.3.34678251..1.4.5.235823194678639241754.51..6.212.5.63.4
A6: 7,9,5                                # reduction candidate for 7,9
A6: 7,9                                  # 13 pairs
* RESTART
* PAIR A1: 7,9 COL A
A6: 7,9,5                                # reduction candidate for 7,9
A6: 5 => CTR
* 7386492512518..946694251.3.946782513.1.4...2..8231.46.8639241754.51..6.212.5..3.4
* PAIR RESTART
* PAIR B3: 7,9 ROW 3
G3: 7,9,8                                # reduction candidate for 7,9
G3: 7,9 => SOLVED
* 738649251251873946694251738346782519517496823982315467863924175475138692129567384
* DURATION: 0:00:05.659849  START: 10:41:43.184912  END: 10:41:48.844761 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-229-base-pr-001.dot
* REASONING
* DIS # A5: 7,9 => CTR => A5: 3,5
* DIS A5: 3,5 # A6: 5 => CTR => A6: 7,9
* PRF A5: 3,5 + A6: 7,9 # G3: 7,9 => SOL
* STA A5: 3,5 + A6: 7,9 + G3: 7,9
* CNT   3 HDP CHAINS /   5 HYP OPENED

Header Info

Top 500 Minimum 17 229

solution: 738649251251873946694251738346782519517496823982315467863924175475138692129567384
info: 2065     FNWXY    S8.f     10313

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

Solution

position: 738649251251873946694251738346782519517496823982315467863924175475138692129567384 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 # A5: 7,9 => CTR => A5: 3,5
* INC # A5: 3,5 => UNS
* INC # A6: 7,9 => UNS
* INC # G3: 7,9 => UNS
* INC # I3: 7,9 => UNS
* INC # E2: 7,9 => UNS
* INC # F2: 7,9 => UNS
* INC # G3: 7,9 => UNS
* INC # I3: 7,9 => UNS
* INC # E2: 7,9 => UNS
* INC # F2: 7,9 => UNS
* INC # G5: 7,9 => UNS
* INC # G5: 8 => UNS
* DIS # A5: 3,9 => CTR => A5: 5,7
* INC # A5: 5,7 => UNS
* INC # I4: 3,9 => UNS
* INC # I4: 8 => UNS
* DIS # A5: 7,9 => CTR => A5: 3,5
* INC # A5: 3,5 => UNS
* INC # A6: 7,9 => UNS
* INC # G5: 7,9 => UNS
* DIS # I5: 7,9 => CTR => I5: 3,8
* INC # I5: 3,8 => UNS
* INC # E5: 8,9 => UNS
* INC # F5: 8,9 => UNS
* INC # I4: 8,9 => UNS
* DIS # I4: 3 => CTR => I4: 8,9
* DIS # F5: 5,9 => CTR => F5: 6,8
* INC # F5: 6,8 => UNS
* INC # A6: 5,9 => UNS
* DIS # A6: 7 => CTR => A6: 5,9
* INC # G5: 7,9 => UNS
* DIS # I5: 7,9 => CTR => I5: 3,8
* INC # I5: 3,8 => UNS
* INC # A6: 7,9 => UNS
* DIS # A6: 5 => CTR => A6: 7,9
* INC # I3: 7,9 => UNS
* INC # I3: 8 => UNS
* CNT  38 HDP CHAINS /  38 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* DIS # A5: 7,9 => CTR => A5: 3,5
* INC A5: 3,5 # A6: 7,9 => UNS
* INC A5: 3,5 # A6: 7,9 => UNS
* DIS A5: 3,5 # A6: 5 => CTR => A6: 7,9
* PRF A5: 3,5 + A6: 7,9 # G3: 7,9 => SOL
* STA A5: 3,5 + A6: 7,9 + G3: 7,9
* CNT   5 HDP CHAINS /   5 HYP OPENED