Analysis of xx-top500-301-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: 5.3...2.....41...7.........64.7......8.....1.......3.....1...4.2...3.........5... initial

Autosolve

position: 513..72.482.41.53747.3521..6417.3.2538752.41.952.4137.7351.8.422.8.347511.4275..3 autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* PRF # H3: 6,9 => SOL
* DIS # H3: 8 => CTR => H3: 6,9
* PRF # D1: 6,9 => SOL
* DIS # D1: 8 => CTR => D1: 6,9
* DIS # E1: 6,9 => CTR => E1: 8
* PRF # E1: 8 => SOL
* PRF # H3: 6,9 => SOL
* DIS # H3: 8 => CTR => H3: 6,9
* PRF # D1: 6,9 => SOL
* DIS # D1: 8 => CTR => D1: 6,9
* DIS # E1: 6,9 => CTR => E1: 8
* PRF # E1: 8 => SOL
* DIS # H3: 8,9 => CTR => H3: 6
* PRF # H3: 6 => SOL
* PRF # E1: 8,9 => SOL
* DIS # E1: 6 => CTR => E1: 8,9
* PRF # D1: 6,8 => SOL
* DIS # D1: 9 => CTR => D1: 6,8
* DIS # G9: 8,9 => CTR => G9: 6
* PRF # G9: 6 => SOL
* PRF # G9: 6,9 => SOL
* DIS # G9: 8 => CTR => G9: 6,9
* DIS # E1: 6,9 => CTR => E1: 8
* PRF # E1: 8 => SOL
* PRF # D1: 6,9 => SOL
* DIS # D1: 8 => CTR => D1: 6,9
* PRF # G9: 6,9 => SOL
* DIS # G9: 8 => CTR => G9: 6,9
* DIS # G9: 8,9 => CTR => G9: 6
* PRF # G9: 6 => SOL
* DIS # H3: 8,9 => CTR => H3: 6
* PRF # H3: 6 => SOL
* CNT  32 HDP CHAINS /  32 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 # H3: 6,9 => SOL
* STA H3: 6,9
* CNT   1 HDP CHAINS /   1 HYP OPENED

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

Details

Positions

5.3...2.....41...7.........64.7......8.....1.......3.....1...4.2...3.........5... initial
513..72.482.41.53747.3521..6417.3.2538752.41.952.4137.7351.8.422.8.347511.4275..3 autosolve
513687294826419537479352168641793825387526419952841376735168942268934751194275683 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (17)
C2: 6,9
C3: 6,9
F2: 6,9
H1: 6,9
I3: 8,9
E4: 8,9
F5: 6,9
D6: 6,8
G4: 8,9
I5: 6,9
I6: 6,8
B8: 6,9
B9: 6,9
E7: 6,9
D8: 6,9
G7: 6,9
H9: 8,9

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
C2,C3: 6.. / C2 = 6  =>  0 pairs (*) / C3 = 6  =>  0 pairs (X)
H1,H3: 6.. / H1 = 6  =>  0 pairs (X) / H3 = 6  =>  0 pairs (_)
F5,D6: 6.. / F5 = 6  =>  0 pairs (*) / D6 = 6  =>  0 pairs (X)
I5,I6: 6.. / I5 = 6  =>  0 pairs (X) / I6 = 6  =>  0 pairs (_)
B8,B9: 6.. / B8 = 6  =>  0 pairs (*) / B9 = 6  =>  0 pairs (X)
E7,D8: 6.. / E7 = 6  =>  0 pairs (*) / D8 = 6  =>  0 pairs (X)
G7,G9: 6.. / G7 = 6  =>  0 pairs (X) / G9 = 6  =>  0 pairs (_)
C2,F2: 6.. / C2 = 6  =>  0 pairs (*) / F2 = 6  =>  0 pairs (X)
C3,H3: 6.. / C3 = 6  =>  0 pairs (X) / H3 = 6  =>  0 pairs (_)
F5,I5: 6.. / F5 = 6  =>  0 pairs (*) / I5 = 6  =>  0 pairs (X)
D6,I6: 6.. / D6 = 6  =>  0 pairs (X) / I6 = 6  =>  0 pairs (_)
E7,G7: 6.. / E7 = 6  =>  0 pairs (*) / G7 = 6  =>  0 pairs (X)
B8,D8: 6.. / B8 = 6  =>  0 pairs (*) / D8 = 6  =>  0 pairs (X)
B9,G9: 6.. / B9 = 6  =>  0 pairs (X) / G9 = 6  =>  0 pairs (_)
E1,E7: 6.. / E1 = 6  =>  0 pairs (X) / E7 = 6  =>  0 pairs (_)
F2,F5: 6.. / F2 = 6  =>  0 pairs (X) / F5 = 6  =>  0 pairs (_)
D1,E1: 8.. / D1 = 8  =>  0 pairs (X) / E1 = 8  =>  0 pairs (_)
H3,I3: 8.. / H3 = 8  =>  0 pairs (X) / I3 = 8  =>  0 pairs (_)
E4,D6: 8.. / E4 = 8  =>  0 pairs (X) / D6 = 8  =>  0 pairs (_)
G4,I6: 8.. / G4 = 8  =>  0 pairs (*) / I6 = 8  =>  0 pairs (X)
G9,H9: 8.. / G9 = 8  =>  0 pairs (X) / H9 = 8  =>  0 pairs (_)
E4,G4: 8.. / E4 = 8  =>  0 pairs (X) / G4 = 8  =>  0 pairs (_)
D6,I6: 8.. / D6 = 8  =>  0 pairs (*) / I6 = 8  =>  0 pairs (X)
D1,D6: 8.. / D1 = 8  =>  0 pairs (X) / D6 = 8  =>  0 pairs (_)
E1,E4: 8.. / E1 = 8  =>  0 pairs (*) / E4 = 8  =>  0 pairs (X)
G4,G9: 8.. / G4 = 8  =>  0 pairs (*) / G9 = 8  =>  0 pairs (X)
H3,H9: 8.. / H3 = 8  =>  0 pairs (X) / H9 = 8  =>  0 pairs (_)
I3,I6: 8.. / I3 = 8  =>  0 pairs (*) / I6 = 8  =>  0 pairs (X)
C2,C3: 9.. / C2 = 9  =>  0 pairs (X) / C3 = 9  =>  0 pairs (_)
E4,F5: 9.. / E4 = 9  =>  0 pairs (*) / F5 = 9  =>  0 pairs (X)
G4,I5: 9.. / G4 = 9  =>  0 pairs (X) / I5 = 9  =>  0 pairs (_)
B8,B9: 9.. / B8 = 9  =>  0 pairs (X) / B9 = 9  =>  0 pairs (_)
E7,D8: 9.. / E7 = 9  =>  0 pairs (X) / D8 = 9  =>  0 pairs (_)
C2,F2: 9.. / C2 = 9  =>  0 pairs (X) / F2 = 9  =>  0 pairs (_)
E4,G4: 9.. / E4 = 9  =>  0 pairs (*) / G4 = 9  =>  0 pairs (X)
F5,I5: 9.. / F5 = 9  =>  0 pairs (X) / I5 = 9  =>  0 pairs (_)
E7,G7: 9.. / E7 = 9  =>  0 pairs (X) / G7 = 9  =>  0 pairs (_)
B8,D8: 9.. / B8 = 9  =>  0 pairs (X) / D8 = 9  =>  0 pairs (_)
D1,D8: 9.. / D1 = 9  =>  0 pairs (X) / D8 = 9  =>  0 pairs (_)
F2,F5: 9.. / F2 = 9  =>  0 pairs (*) / F5 = 9  =>  0 pairs (X)
I3,I5: 9.. / I3 = 9  =>  0 pairs (X) / I5 = 9  =>  0 pairs (_)
* DURATION: 0:01:21.235477  START: 13:14:34.043524  END: 13:15:55.279001 2017-05-04
* CP COUNT: (41)
* SOLUTION FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (B8,B9,C2,C3,D6,D8,E4,E7,F2,F5,G4,G7,H1,H9,I3,I5,I6)
* 513..72.482.41.53747.3521..6417.3.2538752.41.952.4137.7351.8.422.8.347511.4275..3
* PAIR C3: 6,9 ROW 3
H3: 6,9,8                                # reduction candidate for 6,9
H3: 6,9 => SOLVED
* 513687294826419537479352168641793825387526419952841376735168942268934751194275683
H3: 8 => CTR
* 513..726482.4165374763521896417.39253875294169526413787351.8.422.8.347511.4275..3
* PAIR F2: 6,9 BLK 2
D1: 6,9,8                                # reduction candidate for 6,9
D1: 6,9 => SOLVED
* 513687294826419537479352168641793825387526419952841376735168942268934751194275683
D1: 8 => CTR
* 5138.72.482.41.53747.3521..6417839253875294169526413787351.8.422.8.347511.4275..3
E1: 6,9,8                                # reduction candidate for 6,9
E1: 6,9 => CTR
* 5138.72.482.41.53747.3521..6417839253875294169526413787351.8.422.8.347511.4275..3
E1: 8 => SOLVED
* 513687294826419537479352168641793825387526419952841376735168942268934751194275683
* PAIR H1: 6,9 BLK 3
H3: 6,9,8                                # reduction candidate for 6,9
H3: 6,9 => SOLVED
* 513687294826419537479352168641793825387526419952841376735168942268934751194275683
H3: 8 => CTR
* 513..726482.4165374763521896417.39253875294169526413787351.8.422.8.347511.4275..3
* PAIR H1: 6,9 ROW 1
D1: 6,9,8                                # reduction candidate for 6,9
D1: 6,9 => SOLVED
* 513687294826419537479352168641793825387526419952841376735168942268934751194275683
D1: 8 => CTR
* 5138.72.482.41.53747.3521..6417839253875294169526413787351.8.422.8.347511.4275..3
E1: 6,9,8                                # reduction candidate for 6,9
E1: 6,9 => CTR
* 5138.72.482.41.53747.3521..6417839253875294169526413787351.8.422.8.347511.4275..3
E1: 8 => SOLVED
* 513687294826419537479352168641793825387526419952841376735168942268934751194275683
* PAIR I3: 8,9 BLK 3
H3: 8,9,6                                # reduction candidate for 8,9
H3: 8,9 => CTR
* 513..726482.4165374763521..6417.3.253875294169526413787351689422.8.347511.4275..3
H3: 6 => SOLVED
* 513687294826419537479352168641793825387526419952841376735168942268934751194275683
* PAIR E4: 8,9 COL E
E1: 8,9,6                                # reduction candidate for 8,9
E1: 8,9 => SOLVED
* 513687294826419537479352168641793825387526419952841376735168942268934751194275683
E1: 6 => CTR
* 5138672948264195374793521686417.3.2538752.41.952.4137.7351.8.422.8.347511.4275..3
* PAIR D6: 6,8 COL D
D1: 6,8,9                                # reduction candidate for 6,8
D1: 6,8 => SOLVED
* 513687294826419537479352168641793825387526419952841376735168942268934751194275683
D1: 9 => CTR
* 5139872648294165374763521..641793.2538752.41.952.4137.7351.8.422.8.347511.4275..3
* PAIR G4: 8,9 COL G
G9: 8,9,6                                # reduction candidate for 8,9
G9: 8,9 => CTR
* 5139.72.482.41.53747.3521..6417.3.2538752.41.952.4137.7351.86422.8634751164275..3
G9: 6 => SOLVED
* 513687294826419537479352168641793825387526419952841376735168942268934751194275683
* PAIR B9: 6,9 ROW 9
G9: 6,9,8                                # reduction candidate for 6,9
G9: 6,9 => SOLVED
* 513687294826419537479352168641793825387526419952841376735168942268934751194275683
G9: 8 => CTR
* 513..72.482.41.53747.3521..6417.3.2538752.41.952.4137.7351.86422.8634751164275893
* PAIR E7: 6,9 COL E
E1: 6,9,8                                # reduction candidate for 6,9
E1: 6,9 => CTR
* 5138.72.482.41.53747.3521..6417839253875294169526413787351.8.422.8.347511.4275..3
E1: 8 => SOLVED
* 513687294826419537479352168641793825387526419952841376735168942268934751194275683
* PAIR D8: 6,9 COL D
D1: 6,9,8                                # reduction candidate for 6,9
D1: 6,9 => SOLVED
* 513687294826419537479352168641793825387526419952841376735168942268934751194275683
D1: 8 => CTR
* 5138.72.482.41.53747.3521..6417839253875294169526413787351.8.422.8.347511.4275..3
* PAIR G7: 6,9 BLK 9
G9: 6,9,8                                # reduction candidate for 6,9
G9: 6,9 => SOLVED
* 513687294826419537479352168641793825387526419952841376735168942268934751194275683
G9: 8 => CTR
* 513..72.482.41.53747.3521..6417.3.2538752.41.952.4137.7351.86422.8634751164275893
* PAIR H9: 8,9 BLK 9
G9: 8,9,6                                # reduction candidate for 8,9
G9: 8,9 => CTR
* 5139.72.482.41.53747.3521..6417.3.2538752.41.952.4137.7351.86422.8634751164275..3
G9: 6 => SOLVED
* 513687294826419537479352168641793825387526419952841376735168942268934751194275683
* PAIR H9: 8,9 COL H
H3: 8,9,6                                # reduction candidate for 8,9
H3: 8,9 => CTR
* 513..726482.4165374763521..6417.3.253875294169526413787351689422.8.347511.4275..3
H3: 6 => SOLVED
* 513687294826419537479352168641793825387526419952841376735168942268934751194275683
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-301-base-pr-000.dot
* REASONING
* PRF # H3: 6,9 => SOL
* DIS # H3: 8 => CTR => H3: 6,9
* PRF # D1: 6,9 => SOL
* DIS # D1: 8 => CTR => D1: 6,9
* DIS # E1: 6,9 => CTR => E1: 8
* PRF # E1: 8 => SOL
* PRF # H3: 6,9 => SOL
* DIS # H3: 8 => CTR => H3: 6,9
* PRF # D1: 6,9 => SOL
* DIS # D1: 8 => CTR => D1: 6,9
* DIS # E1: 6,9 => CTR => E1: 8
* PRF # E1: 8 => SOL
* DIS # H3: 8,9 => CTR => H3: 6
* PRF # H3: 6 => SOL
* PRF # E1: 8,9 => SOL
* DIS # E1: 6 => CTR => E1: 8,9
* PRF # D1: 6,8 => SOL
* DIS # D1: 9 => CTR => D1: 6,8
* DIS # G9: 8,9 => CTR => G9: 6
* PRF # G9: 6 => SOL
* PRF # G9: 6,9 => SOL
* DIS # G9: 8 => CTR => G9: 6,9
* DIS # E1: 6,9 => CTR => E1: 8
* PRF # E1: 8 => SOL
* PRF # D1: 6,9 => SOL
* DIS # D1: 8 => CTR => D1: 6,9
* PRF # G9: 6,9 => SOL
* DIS # G9: 8 => CTR => G9: 6,9
* DIS # G9: 8,9 => CTR => G9: 6
* PRF # G9: 6 => SOL
* DIS # H3: 8,9 => CTR => H3: 6
* PRF # H3: 6 => SOL
* CNT  32 HDP CHAINS /  32 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (B8,B9,C2,C3,D6,D8,E4,E7,F2,F5,G4,G7,H1,H9,I3,I5,I6)
* 513..72.482.41.53747.3521..6417.3.2538752.41.952.4137.7351.8.422.8.347511.4275..3
* PAIR C3: 6,9 ROW 3
H3: 6,9,8                                # reduction candidate for 6,9
H3: 6,9 => SOLVED
* 513687294826419537479352168641793825387526419952841376735168942268934751194275683
* DURATION: 0:00:02.117456  START: 13:16:35.755980  END: 13:16:37.873436 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-301-base-pr-001.dot
* REASONING
* PRF # H3: 6,9 => SOL
* STA H3: 6,9
* CNT   1 HDP CHAINS /   1 HYP OPENED

Header Info

Top 500 Minimum 17 301

solution: 513687294826419537479352168641793825387526419952841376735168942268934751194275683
info: 2582     FNBWY    S8.f     33306

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

Solution

position: 513687294826419537479352168641793825387526419952841376735168942268934751194275683 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:

* PRF # H3: 6,9 => SOL
* DIS # H3: 8 => CTR => H3: 6,9
* PRF # D1: 6,9 => SOL
* DIS # D1: 8 => CTR => D1: 6,9
* DIS # E1: 6,9 => CTR => E1: 8
* PRF # E1: 8 => SOL
* PRF # H3: 6,9 => SOL
* DIS # H3: 8 => CTR => H3: 6,9
* PRF # D1: 6,9 => SOL
* DIS # D1: 8 => CTR => D1: 6,9
* DIS # E1: 6,9 => CTR => E1: 8
* PRF # E1: 8 => SOL
* DIS # H3: 8,9 => CTR => H3: 6
* PRF # H3: 6 => SOL
* PRF # E1: 8,9 => SOL
* DIS # E1: 6 => CTR => E1: 8,9
* PRF # D1: 6,8 => SOL
* DIS # D1: 9 => CTR => D1: 6,8
* DIS # G9: 8,9 => CTR => G9: 6
* PRF # G9: 6 => SOL
* PRF # G9: 6,9 => SOL
* DIS # G9: 8 => CTR => G9: 6,9
* DIS # E1: 6,9 => CTR => E1: 8
* PRF # E1: 8 => SOL
* PRF # D1: 6,9 => SOL
* DIS # D1: 8 => CTR => D1: 6,9
* PRF # G9: 6,9 => SOL
* DIS # G9: 8 => CTR => G9: 6,9
* DIS # G9: 8,9 => CTR => G9: 6
* PRF # G9: 6 => SOL
* DIS # H3: 8,9 => CTR => H3: 6
* PRF # H3: 6 => SOL
* CNT  32 HDP CHAINS /  32 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* PRF # H3: 6,9 => SOL
* STA H3: 6,9
* CNT   1 HDP CHAINS /   1 HYP OPENED