Analysis of zz-www.sudokuoftheday.co.uk-20060610-absurd-base.sdk
Contents
Sudoku from http://www.sudokuoftheday.co.uk/cgi-bin/sudoku1280.cgi?ACTION=archive2&USER=&MONTH=Jun&YEAR=2006
level: medium
position: ..24....5..465.8...............2..91..6.....2.13...46..3.1..2..7...45...4.5..3.7. initial
Autosolve
position: ..24...15..465182.15...2.4..4..26.91..6.14..22135..46..3.1..2547.1.45...4.5..317. autosolve
Pair Reduction Variants
Pair Reduction Analysis
The following important HDP chains were detected:
* DIS # A1: 3,9 => CTR => A1: 6,8 * DIS # I2: 7 => CTR => I2: 3,9 * DIS # B1: 7,9 => CTR => B1: 6,8 * DIS # I2: 3 => CTR => I2: 7,9 * DIS # B5: 8 => CTR => B5: 7,9 * DIS # D4: 7,8 => CTR => D4: 3 * PRF # C3: 9 => SOL * DIS # C3: 7 => CTR => C3: 8,9 * CNT 8 HDP CHAINS / 32 HYP OPENED
See Appendix: Full HDP Chains for full list of HDP chains.
Pair Reduction
The following important HDP chains were detected:
* DIS # A1: 3,9 => CTR => A1: 6,8 * DIS A1: 6,8 # B1: 7,9 => CTR => B1: 6,8 * DIS A1: 6,8 + B1: 6,8 # B5: 8 => CTR => B5: 7,9 * PRF A1: 6,8 + B1: 6,8 + B5: 7,9 # A5: 5,8 => SOL * STA A1: 6,8 + B1: 6,8 + B5: 7,9 + A5: 5,8 * CNT 4 HDP CHAINS / 5 HYP OPENED
See Appendix: Full HDP Chains for full list of HDP chains.
Details
Positions
| ..24....5..465.8...............2..91..6.....2.13...46..3.1..2..7...45...4.5..3.7. | initial |
| ..24...15..465182.15...2.4..4..26.91..6.14..22135..46..3.1..2547.1.45...4.5..317. | autosolve |
| 682439715374651829159872643847326591596714382213598467938167254761245938425983176 | solved |
Classification
level: medium
Pairing Analysis
-------------------------------------------------- * PAIRS (8) A2: 3,9 B2: 7,9 A4: 5,8 C4: 7,8 H5: 3,8 I6: 7,8 C7: 8,9 H8: 3,8 -------------------------------------------------- * CONSTRAINT PAIRS (AUTO SOLVE) B8,B9: 2.. / B8 = 2 => 10 pairs (_) / B9 = 2 => 9 pairs (_) D8,D9: 2.. / D8 = 2 => 9 pairs (_) / D9 = 2 => 10 pairs (_) B8,D8: 2.. / B8 = 2 => 10 pairs (_) / D8 = 2 => 9 pairs (_) B9,D9: 2.. / B9 = 2 => 9 pairs (_) / D9 = 2 => 10 pairs (_) A1,A2: 3.. / A1 = 3 => 0 pairs (X) / A2 = 3 => 8 pairs (_) E1,E3: 3.. / E1 = 3 => 11 pairs (_) / E3 = 3 => 8 pairs (_) D4,D5: 3.. / D4 = 3 => 14 pairs (_) / D5 = 3 => 0 pairs (X) A2,I2: 3.. / A2 = 3 => 8 pairs (_) / I2 = 3 => 0 pairs (X) D4,G4: 3.. / D4 = 3 => 14 pairs (_) / G4 = 3 => 0 pairs (X) H5,H8: 3.. / H5 = 3 => 0 pairs (X) / H8 = 3 => 15 pairs (_) A4,A5: 5.. / A4 = 5 => 9 pairs (_) / A5 = 5 => 12 pairs (_) G4,G5: 5.. / G4 = 5 => 12 pairs (_) / G5 = 5 => 9 pairs (_) A4,G4: 5.. / A4 = 5 => 9 pairs (_) / G4 = 5 => 12 pairs (_) A5,G5: 5.. / A5 = 5 => 12 pairs (_) / G5 = 5 => 9 pairs (_) A1,B1: 6.. / A1 = 6 => 14 pairs (_) / B1 = 6 => 9 pairs (_) G3,I3: 6.. / G3 = 6 => 9 pairs (_) / I3 = 6 => 13 pairs (_) E7,E9: 6.. / E7 = 6 => 14 pairs (_) / E9 = 6 => 9 pairs (_) A7,E7: 6.. / A7 = 6 => 9 pairs (_) / E7 = 6 => 14 pairs (_) A1,A7: 6.. / A1 = 6 => 14 pairs (_) / A7 = 6 => 9 pairs (_) G3,G8: 6.. / G3 = 6 => 9 pairs (_) / G8 = 6 => 13 pairs (_) C4,B5: 7.. / C4 = 7 => 11 pairs (_) / B5 = 7 => 0 pairs (X) E7,F7: 7.. / E7 = 7 => 11 pairs (_) / F7 = 7 => 10 pairs (_) B2,I2: 7.. / B2 = 7 => 11 pairs (_) / I2 = 7 => 0 pairs (X) C3,C4: 7.. / C3 = 7 => 0 pairs (X) / C4 = 7 => 11 pairs (_) H5,I6: 8.. / H5 = 8 => 15 pairs (_) / I6 = 8 => 0 pairs (X) H5,H8: 8.. / H5 = 8 => 15 pairs (_) / H8 = 8 => 0 pairs (X) A5,B5: 9.. / A5 = 9 => 11 pairs (_) / B5 = 9 => 14 pairs (_) E6,F6: 9.. / E6 = 9 => 10 pairs (_) / F6 = 9 => 11 pairs (_) C3,C7: 9.. / C3 = 9 => 0 pairs (*) / C7 = 9 => 0 pairs (X) * DURATION: 0:00:30.588920 START: 23:44:49.044960 END: 23:45:19.633880 2019-04-30 * CP COUNT: (29) * SOLUTION FOUND -------------------------------------------------- * PREPARE PR GRAPH * PAIR REDUCTION .. * LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A2,A4,B2,C4,C7,H5,H8,I6) * ..24...15..465182.15...2.4..4..26.91..6.14..22135..46..3.1..2547.1.45...4.5..317. * PAIR A2: 3,9 BLK 1 A1: 3,9,6,8 # reduction candidate for 3,9 A1: 3,9 => CTR * .624...15.7465182.1587.2.4..47.26.91.96.147.22135..46.6391..2547.1.45...4.5.6317. A1: 6,8 # 9 pairs * PAIR A2: 3,9 ROW 2 I2: 3,9,7 # reduction candidate for 3,9 I2: 7 => CTR * ..24...15394651827157982.4.5483267919768145322135.9468.391.82547.1245.8.4.5..317. I2: 3,9 # 11 pairs * PAIR B2: 7,9 BLK 1 B1: 7,9,6,8 # reduction candidate for 7,9 B1: 7,9 => CTR * 6.24...153.465182.158..2.4..47.26.91986.145322135..46..391672547.1.45...4.5..317. B1: 6,8 # 9 pairs C3: 7,9,8 # reduction candidate for 7,9 C3: 7,9 # 12 pairs * PAIR B2: 7,9 ROW 2 I2: 7,9,3 # reduction candidate for 7,9 I2: 3 => CTR * 3624...15974651823158732.4..47.26.91.96.147.22135..46.6391..2547.1.45...4.5.6317. I2: 7,9 # 8 pairs * PAIR B2: 7,9 COL B B5: 7,9,8 # reduction candidate for 7,9 B5: 8 => CTR * ..24...15..465182.15...2.4..47.26.91986.145322135..46..3.1..2547.1.45...4.5..317. B5: 7,9 # 11 pairs * PAIR A4: 5,8 BLK 4 A5: 5,8,9 # reduction candidate for 5,8 A5: 5,8 # 14 pairs A5: 9 # 11 pairs * PAIR C4: 7,8 BLK 4 B5: 7,8,9 # reduction candidate for 7,8 B5: 9 # 14 pairs B5: 7,8 # 11 pairs * PAIR C4: 7,8 ROW 4 D4: 7,8,3 # reduction candidate for 7,8 D4: 7,8 => CTR * ..24...15.7465182.15...2.4.54..26391..63145822135..467.3.1..2547.1.45.3.4.5..317. D4: 3 # 14 pairs * PAIR C4: 7,8 COL C C3: 7,8,9 # reduction candidate for 7,8 C3: 9 => SOLVED * 682439715374651829159872643847326591596714382213598467938167254761245938425983176 C3: 7,8 # 10 pairs * PAIR H5: 3,8 ROW 5 D5: 3,8,7 # reduction candidate for 3,8 D5: 7 # 15 pairs D5: 3,8 # 15 pairs * PAIR I6: 7,8 ROW 6 E6: 7,8,9 # reduction candidate for 7,8 E6: 7,8 # 11 pairs F6: 7,8,9 # reduction candidate for 7,8 F6: 7,8 # 10 pairs * PAIR C7: 8,9 BLK 7 A7: 8,9,6 # reduction candidate for 8,9 A7: 8,9 # 14 pairs B8: 8,9,2,6 # reduction candidate for 8,9 B8: 8,9 # 11 pairs B9: 8,9,2,6 # reduction candidate for 8,9 B9: 8,9 # 11 pairs * PAIR C7: 8,9 ROW 7 E7: 8,9,6,7 # reduction candidate for 8,9 E7: 8,9 # 12 pairs F7: 8,9,7 # reduction candidate for 8,9 F7: 8,9 # 11 pairs * PAIR C7: 8,9 COL C C3: 8,9,7 # reduction candidate for 8,9 C3: 7 => CTR * ..24...15.94651827157..2.4.5487263919763145822135..46..391..2547.1.45...4.5..317. C3: 8,9 # 11 pairs * PAIR H8: 3,8 BLK 9 I8: 3,8,6,9 # reduction candidate for 3,8 I8: 3,8 # 12 pairs I8: 6,9 # 10 pairs * INCONCLUSIVE * SAVE PR GRAPH zz-www.sudokuoftheday.co.uk-20060610-absurd-base-pr-000.dot * REASONING * DIS # A1: 3,9 => CTR => A1: 6,8 * DIS # I2: 7 => CTR => I2: 3,9 * DIS # B1: 7,9 => CTR => B1: 6,8 * DIS # I2: 3 => CTR => I2: 7,9 * DIS # B5: 8 => CTR => B5: 7,9 * DIS # D4: 7,8 => CTR => D4: 3 * PRF # C3: 9 => SOL * DIS # C3: 7 => CTR => C3: 8,9 * CNT 8 HDP CHAINS / 32 HYP OPENED -------------------------------------------------- * PREPARE PR GRAPH * PAIR REDUCTION .. * LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A2,A4,B2,C4,C7,H5,H8,I6) * ..24...15..465182.15...2.4..4..26.91..6.14..22135..46..3.1..2547.1.45...4.5..317. * PAIR A2: 3,9 BLK 1 A1: 3,9,6,8 # reduction candidate for 3,9 A1: 3,9 => CTR * .624...15.7465182.1587.2.4..47.26.91.96.147.22135..46.6391..2547.1.45...4.5.6317. * PAIR B2: 7,9 BLK 1 B1: 7,9,6,8 # reduction candidate for 7,9 B1: 7,9 => CTR * 6.24...153.465182.158..2.4..47.26.91986.145322135..46..391672547.1.45...4.5..317. * RESTART * PAIR B2: 7,9 COL B B5: 7,9,8 # reduction candidate for 7,9 B5: 8 => CTR * ..24...15374651829159..2.4..47.26.91986.145322135..46..3.1..2547.1.45...4.5..317. * PAIR RESTART * PAIR A4: 5,8 BLK 4 A5: 5,8,9 # reduction candidate for 5,8 A5: 5,8 => SOLVED * 682439715374651829159872643847326591596714382213598467938167254761245938425983176 * DURATION: 0:00:04.879988 START: 23:45:38.385949 END: 23:45:43.265937 2019-04-30 * SOLUTION FOUND * SAVE PR GRAPH zz-www.sudokuoftheday.co.uk-20060610-absurd-base-pr-001.dot * REASONING * DIS # A1: 3,9 => CTR => A1: 6,8 * DIS A1: 6,8 # B1: 7,9 => CTR => B1: 6,8 * DIS A1: 6,8 + B1: 6,8 # B5: 8 => CTR => B5: 7,9 * PRF A1: 6,8 + B1: 6,8 + B5: 7,9 # A5: 5,8 => SOL * STA A1: 6,8 + B1: 6,8 + B5: 7,9 + A5: 5,8 * CNT 4 HDP CHAINS / 5 HYP OPENED
Header Info
http://www.sudokuoftheday.co.uk/cgi-bin/sudoku1280.cgi?ACTION=archive2&USER=&MONTH=Jun&YEAR=2006, 20060610, absurd
Solution
position: 682439715374651829159872643847326591596714382213598467938167254761245938425983176 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:
* DIS # A1: 3,9 => CTR => A1: 6,8 * INC # A1: 6,8 => UNS * INC # I2: 3,9 => UNS * DIS # I2: 7 => CTR => I2: 3,9 * DIS # B1: 7,9 => CTR => B1: 6,8 * INC # B1: 6,8 => UNS * INC # C3: 7,9 => UNS * INC # I2: 7,9 => UNS * DIS # I2: 3 => CTR => I2: 7,9 * INC # B5: 7,9 => UNS * DIS # B5: 8 => CTR => B5: 7,9 * INC # A5: 5,8 => UNS * INC # A5: 9 => UNS * INC # B5: 7,8 => UNS * INC # B5: 9 => UNS * DIS # D4: 7,8 => CTR => D4: 3 * INC # D4: 3 => UNS * INC # C3: 7,8 => UNS * PRF # C3: 9 => SOL * INC # D5: 3,8 => UNS * INC # D5: 7 => UNS * INC # E6: 7,8 => UNS * INC # F6: 7,8 => UNS * INC # A7: 8,9 => UNS * INC # B8: 8,9 => UNS * INC # B9: 8,9 => UNS * INC # E7: 8,9 => UNS * INC # F7: 8,9 => UNS * INC # C3: 8,9 => UNS * DIS # C3: 7 => CTR => C3: 8,9 * INC # I8: 3,8 => UNS * INC # I8: 6,9 => UNS * CNT 32 HDP CHAINS / 32 HYP OPENED
A2. Pair Reduction
Full list of HDP chains traversed:
* DIS # A1: 3,9 => CTR => A1: 6,8 * DIS A1: 6,8 # B1: 7,9 => CTR => B1: 6,8 * INC A1: 6,8 + B1: 6,8 # B5: 7,9 => UNS * DIS A1: 6,8 + B1: 6,8 # B5: 8 => CTR => B5: 7,9 * PRF A1: 6,8 + B1: 6,8 + B5: 7,9 # A5: 5,8 => SOL * STA A1: 6,8 + B1: 6,8 + B5: 7,9 + A5: 5,8 * CNT 5 HDP CHAINS / 5 HYP OPENED