Analysis of xx-top500-275-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: ...3...1..6..5....2........3..6........5..7..1.........7....4.8.5...26......1.... initial

Autosolve

position: 5..327.1676315.2..21..6.3..3..6..1.2.265.17.31..2.3.6.671935428.5.7.2631.32.16... autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* DIS # C1: 8,9 => CTR => C1: 4
* DIS # F3: 4 => CTR => F3: 8,9
* DIS # C8: 4 => CTR => C8: 8,9
* DIS # F3: 4 => CTR => F3: 8,9
* DIS # H2: 4 => CTR => H2: 8,9
* DIS # F3: 9 => CTR => F3: 4,8
* DIS # H2: 4 => CTR => H2: 8,9
* DIS # C1: 8,9 => CTR => C1: 4
* DIS # G6: 5 => CTR => G6: 8,9
* DIS # H2: 4,9 => CTR => H2: 8
* DIS # F3: 9 => CTR => F3: 4,8
* DIS # A8: 4,8 => CTR => A8: 9
* DIS # A5: 9 => CTR => A5: 4,8
* DIS # A8: 4,8 => CTR => A8: 9
* DIS # G6: 5,9 => CTR => G6: 8
* CNT  15 HDP CHAINS /  50 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 # C1: 8,9 => CTR => C1: 4
* DIS C1: 4 # F3: 4 => CTR => F3: 8,9
* DIS C1: 4 + F3: 8,9 # G6: 5 => CTR => G6: 8,9
* PRF C1: 4 + F3: 8,9 + G6: 8,9 # H4: 5 => SOL
* STA C1: 4 + F3: 8,9 + G6: 8,9 + H4: 5
* CNT   4 HDP CHAINS /   8 HYP OPENED

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

Details

Positions

...3...1..6..5....2........3..6........5..7..1.........7....4.8.5...26......1.... initial
5..327.1676315.2..21..6.3..3..6..1.2.265.17.31..2.3.6.671935428.5.7.2631.32.16... autosolve
584327916763159284219468375397684152826591743145273869671935428958742631432816597 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (14)
C3: 8,9
F2: 8,9
D3: 4,8
G1: 8,9
I2: 4,9
H3: 5,7
I3: 5,7
C4: 5,7
C6: 5,7
F4: 4,8
A9: 4,8
E8: 4,8
D9: 4,8
G9: 5,9

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
B1,C1: 4.. / B1 = 4  =>  0 pairs (X) / C1 = 4  => 17 pairs (_)
D3,F3: 4.. / D3 = 4  => 17 pairs (_) / F3 = 4  =>  0 pairs (X)
H2,I2: 4.. / H2 = 4  =>  0 pairs (X) / I2 = 4  => 15 pairs (_)
E8,D9: 4.. / E8 = 4  => 17 pairs (_) / D9 = 4  =>  0 pairs (X)
A9,D9: 4.. / A9 = 4  => 17 pairs (_) / D9 = 4  =>  0 pairs (X)
C1,C8: 4.. / C1 = 4  => 17 pairs (_) / C8 = 4  =>  0 pairs (X)
D3,D9: 4.. / D3 = 4  => 17 pairs (_) / D9 = 4  =>  0 pairs (X)
F3,F4: 4.. / F3 = 4  =>  0 pairs (X) / F4 = 4  => 17 pairs (_)
I2,I6: 4.. / I2 = 4  => 15 pairs (_) / I6 = 4  =>  0 pairs (X)
H3,I3: 5.. / H3 = 5  => 11 pairs (_) / I3 = 5  => 14 pairs (_)
C4,C6: 5.. / C4 = 5  => 13 pairs (_) / C6 = 5  => 14 pairs (_)
C4,H4: 5.. / C4 = 5  => 13 pairs (_) / H4 = 5  => 14 pairs (_)
G6,G9: 5.. / G6 = 5  =>  0 pairs (X) / G9 = 5  => 16 pairs (_)
H3,I3: 7.. / H3 = 7  => 14 pairs (_) / I3 = 7  => 11 pairs (_)
C4,C6: 7.. / C4 = 7  => 14 pairs (_) / C6 = 7  => 13 pairs (_)
E4,E6: 7.. / E4 = 7  => 13 pairs (_) / E6 = 7  => 14 pairs (_)
H9,I9: 7.. / H9 = 7  => 11 pairs (_) / I9 = 7  => 14 pairs (_)
C4,E4: 7.. / C4 = 7  => 14 pairs (_) / E4 = 7  => 13 pairs (_)
C6,E6: 7.. / C6 = 7  => 13 pairs (_) / E6 = 7  => 14 pairs (_)
H3,H9: 7.. / H3 = 7  => 14 pairs (_) / H9 = 7  => 11 pairs (_)
I3,I9: 7.. / I3 = 7  => 11 pairs (_) / I9 = 7  => 14 pairs (_)
G1,H2: 8.. / G1 = 8  =>  0 pairs (X) / H2 = 8  => 19 pairs (_)
E8,D9: 8.. / E8 = 8  =>  0 pairs (X) / D9 = 8  => 17 pairs (_)
F2,H2: 8.. / F2 = 8  =>  0 pairs (X) / H2 = 8  => 19 pairs (_)
A9,D9: 8.. / A9 = 8  =>  0 pairs (X) / D9 = 8  => 17 pairs (_)
D3,D9: 8.. / D3 = 8  =>  0 pairs (X) / D9 = 8  => 17 pairs (_)
G1,G6: 8.. / G1 = 8  =>  0 pairs (X) / G6 = 8  => 19 pairs (_)
F2,F3: 9.. / F2 = 9  => 19 pairs (_) / F3 = 9  =>  0 pairs (X)
A8,C8: 9.. / A8 = 9  => 17 pairs (_) / C8 = 9  =>  0 pairs (X)
C3,F3: 9.. / C3 = 9  => 19 pairs (_) / F3 = 9  =>  0 pairs (X)
A5,A8: 9.. / A5 = 9  =>  0 pairs (X) / A8 = 9  => 17 pairs (_)
* DURATION: 0:01:04.346147  START: 12:19:41.647972  END: 12:20:45.994119 2017-05-04
* CP COUNT: (31)
* CLUE FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A9,C3,C4,C6,D3,D9,E8,F2,F4,G1,G9,H3,I2,I3)
* 5..327.1676315.2..21..6.3..3..6..1.2.265.17.31..2.3.6.671935428.5.7.2631.32.16...
* PAIR C3: 8,9 BLK 1
B1: 8,9,4                                # reduction candidate for 8,9
B1: 8,9                                  # 17 pairs
C1: 8,9,4                                # reduction candidate for 8,9
C1: 8,9 => CTR
* 54.327.1676315.2..21.8643..3..6.81.242659178318.2.3.6.671935428954782631832416...
C1: 4                                    # 17 pairs
* PAIR C3: 8,9 ROW 3
F3: 8,9,4                                # reduction candidate for 8,9
F3: 4 => CTR
* 5..327.167631592842198643..3..6.81.28265.17.31..2.386.671935428958742631.32.16...
F3: 8,9                                  # 17 pairs
* PAIR C3: 8,9 COL C
C8: 8,9,4                                # reduction candidate for 8,9
C8: 4 => CTR
* 54.327.1676315.2..21.8643..3..6.81.242659178318.2.3.6.671935428954782631832416...
C8: 8,9                                  # 17 pairs
* PAIR F2: 8,9 BLK 2
F3: 8,9,4                                # reduction candidate for 8,9
F3: 4 => CTR
* 5..327.167631592842198643..3..6.81.28265.17.31..2.386.671935428958742631.32.16...
F3: 8,9                                  # 17 pairs
* PAIR F2: 8,9 ROW 2
H2: 8,9,4                                # reduction candidate for 8,9
H2: 4 => CTR
* 5..3278167631582492184693..3..6.41.24265.17.31..2.3.646719354289547.2631.32.16...
H2: 8,9                                  # 15 pairs
* PAIR D3: 4,8 BLK 2
F3: 4,8,9                                # reduction candidate for 4,8
F3: 9 => CTR
* 5943278167631582942184693..38.69415292658174314.2.3.6.671935428859742631432816...
F3: 4,8                                  # 19 pairs
* PAIR G1: 8,9 BLK 3
H2: 8,9,4                                # reduction candidate for 8,9
H2: 4 => CTR
* 5..3278167631582492184693..3..6.41.24265.17.31..2.3.646719354289547.2631.32.16...
H2: 8,9                                  # 15 pairs
* PAIR G1: 8,9 ROW 1
B1: 8,9,4                                # reduction candidate for 8,9
B1: 8,9                                  # 17 pairs
C1: 8,9,4                                # reduction candidate for 8,9
C1: 8,9 => CTR
* 54.327.1676315.2..21.8643..3..6.81.242659178318.2.3.6.671935428954782631832416...
C1: 4                                    # 17 pairs
* PAIR G1: 8,9 COL G
G6: 8,9,5                                # reduction candidate for 8,9
G6: 5 => CTR
* 5.43278167631582..2184693..3.56741.2.265.17431472835696719354288597426314328169..
G6: 8,9                                  # 16 pairs
* PAIR I2: 4,9 BLK 3
H2: 4,9,8                                # reduction candidate for 4,9
H2: 4,9 => CTR
* 5.43278167631582..2184693..3..6.41.2.265.174314.283.6.671935428859742631432816...
H2: 8                                    # 19 pairs
* PAIR I2: 4,9 COL I
I6: 4,9,5                                # reduction candidate for 4,9
I6: 4,9                                  # 16 pairs
I6: 5                                    # 10 pairs
* PAIR H3: 5,7 COL H
H9: 5,7,9                                # reduction candidate for 5,7
H9: 9                                    # 14 pairs
H9: 5,7                                  # 13 pairs
* PAIR I3: 5,7 COL I
I9: 5,7,9                                # reduction candidate for 5,7
I9: 5,7                                  # 16 pairs
I9: 9                                    # 10 pairs
* PAIR F4: 4,8 BLK 5
E4: 4,8,7,9                              # reduction candidate for 4,8
E4: 4,8                                  # 18 pairs
E5: 4,8,9                                # reduction candidate for 4,8
E5: 4,8                                  # 17 pairs
E6: 4,8,7,9                              # reduction candidate for 4,8
E6: 4,8                                  # 18 pairs
* PAIR F4: 4,8 ROW 4
B4: 4,8,9                                # reduction candidate for 4,8
B4: 4,8                                  # 19 pairs
H4: 4,8,5,9                              # reduction candidate for 4,8
H4: 4,8                                  # 18 pairs
* PAIR F4: 4,8 COL F
F3: 4,8,9                                # reduction candidate for 4,8
F3: 9 => CTR
* 5943278167631582942184693..38.69415292658174314.2.3.6.671935428859742631432816...
F3: 4,8                                  # 19 pairs
* PAIR A9: 4,8 BLK 7
A8: 4,8,9                                # reduction candidate for 4,8
A8: 4,8 => CTR
* 5943278167631582..2184693..3..6.41.29265817431..2.3.6.671935428.597.2631.32.16...
A8: 9                                    # 17 pairs
C8: 4,8,9                                # reduction candidate for 4,8
C8: 4,8                                  # 17 pairs
* PAIR A9: 4,8 COL A
A5: 4,8,9                                # reduction candidate for 4,8
A5: 9 => CTR
* 5943278167631582..2184693..3..6.41.29265817431..2.3.6.671935428.597.2631.32.16...
A5: 4,8                                  # 17 pairs
* PAIR E8: 4,8 ROW 8
A8: 4,8,9                                # reduction candidate for 4,8
A8: 4,8 => CTR
* 5943278167631582..2184693..3..6.41.29265817431..2.3.6.671935428.597.2631.32.16...
A8: 9                                    # 17 pairs
C8: 4,8,9                                # reduction candidate for 4,8
C8: 4,8                                  # 17 pairs
* PAIR E8: 4,8 COL E
E4: 4,8,7,9                              # reduction candidate for 4,8
E4: 4,8                                  # 18 pairs
E5: 4,8,9                                # reduction candidate for 4,8
E5: 4,8                                  # 17 pairs
E6: 4,8,7,9                              # reduction candidate for 4,8
E6: 4,8                                  # 18 pairs
* PAIR G9: 5,9 BLK 9
H9: 5,9,7                                # reduction candidate for 5,9
H9: 5,9                                  # 14 pairs
I9: 5,9,7                                # reduction candidate for 5,9
I9: 5,9                                  # 11 pairs
* PAIR G9: 5,9 COL G
G6: 5,9,8                                # reduction candidate for 5,9
G6: 5,9 => CTR
* 5.43278167631582..2184693..3..6.41.2.265.174314.283.6.671935428859742631432816...
G6: 8                                    # 19 pairs
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-275-base-pr-000.dot
* REASONING
* DIS # C1: 8,9 => CTR => C1: 4
* DIS # F3: 4 => CTR => F3: 8,9
* DIS # C8: 4 => CTR => C8: 8,9
* DIS # F3: 4 => CTR => F3: 8,9
* DIS # H2: 4 => CTR => H2: 8,9
* DIS # F3: 9 => CTR => F3: 4,8
* DIS # H2: 4 => CTR => H2: 8,9
* DIS # C1: 8,9 => CTR => C1: 4
* DIS # G6: 5 => CTR => G6: 8,9
* DIS # H2: 4,9 => CTR => H2: 8
* DIS # F3: 9 => CTR => F3: 4,8
* DIS # A8: 4,8 => CTR => A8: 9
* DIS # A5: 9 => CTR => A5: 4,8
* DIS # A8: 4,8 => CTR => A8: 9
* DIS # G6: 5,9 => CTR => G6: 8
* CNT  15 HDP CHAINS /  50 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A9,C3,C4,C6,D3,D9,E8,F2,F4,G1,G9,H3,I2,I3)
* 5..327.1676315.2..21..6.3..3..6..1.2.265.17.31..2.3.6.671935428.5.7.2631.32.16...
* PAIR C3: 8,9 BLK 1
B1: 8,9,4                                # reduction candidate for 8,9
B1: 8,9                                  # 17 pairs
C1: 8,9,4                                # reduction candidate for 8,9
C1: 8,9 => CTR
* 54.327.1676315.2..21.8643..3..6.81.242659178318.2.3.6.671935428954782631832416...
* RESTART
* PAIR C3: 8,9 ROW 3
F3: 8,9,4                                # reduction candidate for 8,9
F3: 4 => CTR
* 5.4327.167631592842198643..3..6.81.28265.17.31..2.386.6719354289587.2631.32.16...
* PAIR RESTART
* PAIR G1: 8,9 COL G
G6: 8,9,5                                # reduction candidate for 8,9
G6: 5 => CTR
* 5.43278167631582942184693..38.694152.265.174314.2.3.6.671935428.5.742631432816...
* PAIR RESTART

* LEVEL 0 PASS 1 ROUND 2 (AUTO SOLVE) (A5,A8,B1,B4,C3,C4,C6,C8,E5,F2,F3,G1,G6,H2,H3,H9,I3,I6,I9)
* 5.4327.1676315.2.421.46.3..3..6.41.2.265.174314.2.3.6.671935428.5.7426314328165..
* PAIR H2: 8,9 COL H
H4: 8,9,5                                # reduction candidate for 8,9
H4: 5 => SOLVED
* 584327916763159284219468375397684152826591743145273869671935428958742631432816597
* DURATION: 0:00:11.469503  START: 12:21:40.914805  END: 12:21:52.384308 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-275-base-pr-001.dot
* REASONING
* DIS # C1: 8,9 => CTR => C1: 4
* DIS C1: 4 # F3: 4 => CTR => F3: 8,9
* DIS C1: 4 + F3: 8,9 # G6: 5 => CTR => G6: 8,9
* PRF C1: 4 + F3: 8,9 + G6: 8,9 # H4: 5 => SOL
* STA C1: 4 + F3: 8,9 + G6: 8,9 + H4: 5
* CNT   4 HDP CHAINS /   8 HYP OPENED

Header Info

Top 500 Minimum 17 275

solution: 584327916763159284219468375397684152826591743145273869671935428958742631432816597
info: 2204     FNBHWXY  S8.f     48985

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

Solution

position: 584327916763159284219468375397684152826591743145273869671935428958742631432816597 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 # B1: 8,9 => UNS
* DIS # C1: 8,9 => CTR => C1: 4
* INC # C1: 4 => UNS
* INC # F3: 8,9 => UNS
* DIS # F3: 4 => CTR => F3: 8,9
* INC # C8: 8,9 => UNS
* DIS # C8: 4 => CTR => C8: 8,9
* INC # F3: 8,9 => UNS
* DIS # F3: 4 => CTR => F3: 8,9
* INC # H2: 8,9 => UNS
* DIS # H2: 4 => CTR => H2: 8,9
* INC # F3: 4,8 => UNS
* DIS # F3: 9 => CTR => F3: 4,8
* INC # H2: 8,9 => UNS
* DIS # H2: 4 => CTR => H2: 8,9
* INC # B1: 8,9 => UNS
* DIS # C1: 8,9 => CTR => C1: 4
* INC # C1: 4 => UNS
* INC # G6: 8,9 => UNS
* DIS # G6: 5 => CTR => G6: 8,9
* DIS # H2: 4,9 => CTR => H2: 8
* INC # H2: 8 => UNS
* INC # I6: 4,9 => UNS
* INC # I6: 5 => UNS
* INC # H9: 5,7 => UNS
* INC # H9: 9 => UNS
* INC # I9: 5,7 => UNS
* INC # I9: 9 => UNS
* INC # E4: 4,8 => UNS
* INC # E5: 4,8 => UNS
* INC # E6: 4,8 => UNS
* INC # B4: 4,8 => UNS
* INC # H4: 4,8 => UNS
* INC # F3: 4,8 => UNS
* DIS # F3: 9 => CTR => F3: 4,8
* DIS # A8: 4,8 => CTR => A8: 9
* INC # A8: 9 => UNS
* INC # C8: 4,8 => UNS
* INC # A5: 4,8 => UNS
* DIS # A5: 9 => CTR => A5: 4,8
* DIS # A8: 4,8 => CTR => A8: 9
* INC # A8: 9 => UNS
* INC # C8: 4,8 => UNS
* INC # E4: 4,8 => UNS
* INC # E5: 4,8 => UNS
* INC # E6: 4,8 => UNS
* INC # H9: 5,9 => UNS
* INC # I9: 5,9 => UNS
* DIS # G6: 5,9 => CTR => G6: 8
* INC # G6: 8 => UNS
* CNT  50 HDP CHAINS /  50 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* INC # B1: 8,9 => UNS
* DIS # C1: 8,9 => CTR => C1: 4
* INC C1: 4 # F3: 8,9 => UNS
* DIS C1: 4 # F3: 4 => CTR => F3: 8,9
* INC C1: 4 + F3: 8,9 # G6: 8,9 => UNS
* DIS C1: 4 + F3: 8,9 # G6: 5 => CTR => G6: 8,9
* INC C1: 4 + F3: 8,9 + G6: 8,9 # H4: 8,9 => UNS
* PRF C1: 4 + F3: 8,9 + G6: 8,9 # H4: 5 => SOL
* STA C1: 4 + F3: 8,9 + G6: 8,9 + H4: 5
* CNT   8 HDP CHAINS /   8 HYP OPENED