Analysis of zz-www.sudokuoftheday.co.uk-20060905-absurd-base.sdk
Contents
Sudoku from http://www.sudokuoftheday.co.uk/cgi-bin/sudoku1280.cgi?ACTION=archive2&USER=&MONTH=Sep&YEAR=2006
level: medium
position: ......3..9..8.2.....2....4.......93..1...96....3.7...5.4...7.6.6.....8.45.9.8.7.. initial
Autosolve
position: .8....3929..8.2.76..2....48.....8931.1...96.7.93.7.4.5.4...72696.....854529.8.713 autosolve
Pair Reduction Variants
Pair Reduction Analysis
The following important HDP chains were detected:
* PRF # B3: 3,5 => SOL * DIS # C2: 1,5 => CTR => C2: 4 * PRF # F3: 1,5 => SOL * DIS # F3: 3 => CTR => F3: 1,5 * DIS # A7: 1,8 => CTR => A7: 3 * PRF # A7: 3 => SOL * PRF # B3: 3,7 => SOL * DIS # F3: 5 => CTR => F3: 1,3 * CNT 8 HDP CHAINS / 20 HYP OPENED
See Appendix: Full HDP Chains for full list of HDP chains.
Pair Reduction
The following important HDP chains were detected:
* PRF # B3: 3,5 => SOL * STA B3: 3,5 * CNT 1 HDP CHAINS / 1 HYP OPENED
See Appendix: Full HDP Chains for full list of HDP chains.
Details
Positions
| ......3..9..8.2.....2....4.......93..1...96....3.7...5.4...7.6.6.....8.45.9.8.7.. | initial |
| .8....3929..8.2.76..2....48.....8931.1...96.7.93.7.4.5.4...72696.....854529.8.713 | autosolve |
| 186745392954832176732961548267458931415329687893176425348517269671293854529684713 | solved |
Classification
level: medium
Pairing Analysis
-------------------------------------------------- * PAIRS (16) B2: 3,5 G2: 1,5 G3: 1,5 A6: 2,8 D6: 1,6 F6: 1,6 H5: 2,8 H6: 2,8 C7: 1,8 B8: 3,7 C8: 1,7 D8: 2,9 E8: 2,9 F8: 1,3 D9: 4,6 F9: 4,6 -------------------------------------------------- * CONSTRAINT PAIRS (AUTO SOLVE) G2,G3: 1.. / G2 = 1 => 15 pairs (_) / G3 = 1 => 0 pairs (X) D6,F6: 1.. / D6 = 1 => 15 pairs (_) / F6 = 1 => 0 pairs (X) C8,F8: 1.. / C8 = 1 => 0 pairs (*) / F8 = 1 => 0 pairs (X) H5,H6: 2.. / H5 = 2 => 15 pairs (_) / H6 = 2 => 15 pairs (_) D8,E8: 2.. / D8 = 2 => 16 pairs (_) / E8 = 2 => 16 pairs (_) A6,H6: 2.. / A6 = 2 => 15 pairs (_) / H6 = 2 => 15 pairs (_) D5,E5: 3.. / D5 = 3 => 17 pairs (_) / E5 = 3 => 0 pairs (X) A7,B8: 3.. / A7 = 3 => 0 pairs (*) / B8 = 3 => 0 pairs (X) B2,E2: 3.. / B2 = 3 => 0 pairs (X) / E2 = 3 => 0 pairs (_) B8,F8: 3.. / B8 = 3 => 0 pairs (X) / F8 = 3 => 0 pairs (_) A3,A7: 3.. / A3 = 3 => 0 pairs (X) / A7 = 3 => 0 pairs (_) F3,F8: 3.. / F3 = 3 => 0 pairs (X) / F8 = 3 => 0 pairs (_) D9,F9: 4.. / D9 = 4 => 0 pairs (X) / F9 = 4 => 15 pairs (_) C2,E2: 4.. / C2 = 4 => 19 pairs (_) / E2 = 4 => 0 pairs (X) F1,F9: 4.. / F1 = 4 => 0 pairs (X) / F9 = 4 => 15 pairs (_) F1,F3: 5.. / F1 = 5 => 15 pairs (_) / F3 = 5 => 0 pairs (X) G2,G3: 5.. / G2 = 5 => 0 pairs (X) / G3 = 5 => 15 pairs (_) D7,E7: 5.. / D7 = 5 => 18 pairs (_) / E7 = 5 => 21 pairs (_) C1,F1: 5.. / C1 = 5 => 0 pairs (X) / F1 = 5 => 15 pairs (_) C1,B3: 6.. / C1 = 6 => 18 pairs (_) / B3 = 6 => 17 pairs (_) E1,E3: 6.. / E1 = 6 => 17 pairs (_) / E3 = 6 => 18 pairs (_) B4,C4: 6.. / B4 = 6 => 18 pairs (_) / C4 = 6 => 17 pairs (_) D6,F6: 6.. / D6 = 6 => 0 pairs (X) / F6 = 6 => 15 pairs (_) D9,F9: 6.. / D9 = 6 => 15 pairs (_) / F9 = 6 => 0 pairs (X) C1,E1: 6.. / C1 = 6 => 18 pairs (_) / E1 = 6 => 17 pairs (_) B3,E3: 6.. / B3 = 6 => 17 pairs (_) / E3 = 6 => 18 pairs (_) B3,B4: 6.. / B3 = 6 => 17 pairs (_) / B4 = 6 => 18 pairs (_) C1,C4: 6.. / C1 = 6 => 18 pairs (_) / C4 = 6 => 17 pairs (_) D6,D9: 6.. / D6 = 6 => 0 pairs (X) / D9 = 6 => 15 pairs (_) F6,F9: 6.. / F6 = 6 => 15 pairs (_) / F9 = 6 => 0 pairs (X) D1,D3: 7.. / D1 = 7 => 17 pairs (_) / D3 = 7 => 23 pairs (_) B8,C8: 7.. / B8 = 7 => 0 pairs (*) / C8 = 7 => 0 pairs (X) H5,H6: 8.. / H5 = 8 => 15 pairs (_) / H6 = 8 => 15 pairs (_) A7,C7: 8.. / A7 = 8 => 0 pairs (X) / C7 = 8 => 17 pairs (_) A6,H6: 8.. / A6 = 8 => 15 pairs (_) / H6 = 8 => 15 pairs (_) C5,C7: 8.. / C5 = 8 => 0 pairs (X) / C7 = 8 => 17 pairs (_) D3,E3: 9.. / D3 = 9 => 16 pairs (_) / E3 = 9 => 16 pairs (_) D8,E8: 9.. / D8 = 9 => 16 pairs (_) / E8 = 9 => 16 pairs (_) D3,D8: 9.. / D3 = 9 => 16 pairs (_) / D8 = 9 => 16 pairs (_) E3,E8: 9.. / E3 = 9 => 16 pairs (_) / E8 = 9 => 16 pairs (_) * DURATION: 0:00:52.737574 START: 02:22:44.779787 END: 02:23:37.517361 2019-05-01 * CP COUNT: (40) * SOLUTION FOUND -------------------------------------------------- * PREPARE PR GRAPH * PAIR REDUCTION .. * LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A6,B2,B8,C7,C8,D6,D8,D9,E8,F6,F8,F9,G2,G3,H5,H6) * .8....3929..8.2.76..2....48.....8931.1...96.7.93.7.4.5.4...72696.....854529.8.713 * PAIR B2: 3,5 BLK 1 B3: 3,5,6,7 # reduction candidate for 3,5 B3: 3,5 => SOLVED * 186745392954832176732961548267458931415329687893176425348517269671293854529684713 B3: 6,7 # 17 pairs * PAIR G2: 1,5 ROW 2 C2: 1,5,4 # reduction candidate for 1,5 C2: 1,5 => CTR * .8....392935842176.62...548.56.28931.14..96.7.931764.5348517269671293854529684713 C2: 4 # 19 pairs * PAIR G3: 1,5 ROW 3 F3: 1,5,3 # reduction candidate for 1,5 F3: 1,5 => SOLVED * 186745392954832176732961548267458931415329687893176425348517269671293854529684713 F3: 3 => CTR * .8...53929..8.2.76..2..3.48.....8931.1...96.7.93.7.4.5348..7269671...854529.8.713 * PAIR A6: 2,8 BLK 4 A5: 2,8,4 # reduction candidate for 2,8 A5: 4 # 19 pairs A5: 2,8 # 19 pairs * PAIR H5: 2,8 ROW 5 A5: 2,8,4 # reduction candidate for 2,8 A5: 4 # 19 pairs A5: 2,8 # 19 pairs * PAIR C7: 1,8 BLK 7 A7: 1,8,3 # reduction candidate for 1,8 A7: 1,8 => CTR * .8....3929..8.2.763.2....48.....8931.1...96.7.93.7.4.5.4...7269637..1854529.8.713 A7: 3 => SOLVED * 186745392954832176732961548267458931415329687893176425348517269671293854529684713 * PAIR B8: 3,7 COL B B3: 3,7,5,6 # reduction candidate for 3,7 B3: 3,7 => SOLVED * 186745392954832176732961548267458931415329687893176425348517269671293854529684713 B3: 5,6 # 17 pairs * PAIR C8: 1,7 COL C C1: 1,7,4,5,6 # reduction candidate for 1,7 C1: 1,7 # 19 pairs C1: 4,5,6 # 16 pairs * PAIR F8: 1,3 BLK 8 D7: 1,3,5 # reduction candidate for 1,3 D7: 1,3 # 21 pairs E7: 1,3,5 # reduction candidate for 1,3 E7: 1,3 # 18 pairs * PAIR F8: 1,3 COL F F3: 1,3,5 # reduction candidate for 1,3 F3: 5 => CTR * .85.6.39293.8.2576762..5148.5...8931.1...96.7.93.7.4.5.4...72696....3854529.8.713 F3: 1,3 # 15 pairs * INCONCLUSIVE * SAVE PR GRAPH zz-www.sudokuoftheday.co.uk-20060905-absurd-base-pr-000.dot * REASONING * PRF # B3: 3,5 => SOL * DIS # C2: 1,5 => CTR => C2: 4 * PRF # F3: 1,5 => SOL * DIS # F3: 3 => CTR => F3: 1,5 * DIS # A7: 1,8 => CTR => A7: 3 * PRF # A7: 3 => SOL * PRF # B3: 3,7 => SOL * DIS # F3: 5 => CTR => F3: 1,3 * CNT 8 HDP CHAINS / 20 HYP OPENED -------------------------------------------------- * PREPARE PR GRAPH * PAIR REDUCTION .. * LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A6,B2,B8,C7,C8,D6,D8,D9,E8,F6,F8,F9,G2,G3,H5,H6) * .8....3929..8.2.76..2....48.....8931.1...96.7.93.7.4.5.4...72696.....854529.8.713 * PAIR B2: 3,5 BLK 1 B3: 3,5,6,7 # reduction candidate for 3,5 B3: 3,5 => SOLVED * 186745392954832176732961548267458931415329687893176425348517269671293854529684713 * DURATION: 0:00:01.781611 START: 02:23:53.239307 END: 02:23:55.020918 2019-05-01 * SOLUTION FOUND * SAVE PR GRAPH zz-www.sudokuoftheday.co.uk-20060905-absurd-base-pr-001.dot * REASONING * PRF # B3: 3,5 => SOL * STA B3: 3,5 * CNT 1 HDP CHAINS / 1 HYP OPENED
Header Info
http://www.sudokuoftheday.co.uk/cgi-bin/sudoku1280.cgi?ACTION=archive2&USER=&MONTH=Sep&YEAR=2006, 20060905, absurd
Solution
position: 186745392954832176732961548267458931415329687893176425348517269671293854529684713 solved
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 # B3: 3,5 => SOL * INC # B3: 6,7 => UNS * DIS # C2: 1,5 => CTR => C2: 4 * INC # C2: 4 => UNS * PRF # F3: 1,5 => SOL * DIS # F3: 3 => CTR => F3: 1,5 * INC # A5: 2,8 => UNS * INC # A5: 4 => UNS * INC # A5: 2,8 => UNS * INC # A5: 4 => UNS * DIS # A7: 1,8 => CTR => A7: 3 * PRF # A7: 3 => SOL * PRF # B3: 3,7 => SOL * INC # B3: 5,6 => UNS * INC # C1: 1,7 => UNS * INC # C1: 4,5,6 => UNS * INC # D7: 1,3 => UNS * INC # E7: 1,3 => UNS * INC # F3: 1,3 => UNS * DIS # F3: 5 => CTR => F3: 1,3 * CNT 20 HDP CHAINS / 20 HYP OPENED
A2. Pair Reduction
Full list of HDP chains traversed:
* PRF # B3: 3,5 => SOL * STA B3: 3,5 * CNT 1 HDP CHAINS / 1 HYP OPENED