Analysis of zz-www.sudokuoftheday.co.uk-20060317-absurd-base.sdk
Contents
Sudoku from http://www.sudokuoftheday.co.uk/cgi-bin/sudoku1280.cgi?ACTION=archive2&USER=&MONTH=Mar&YEAR=2006
level: medium
position: ..2...47.1..6....5....32....6.7.3942.9..4......12........1...87.....9..4..6.2.59. initial
Autosolve
position: ..2..147.1.96....5....32....6.71394229..4......129....9..1...87.....9..4..6.2.59. autosolve
Pair Reduction Variants
Pair Reduction Analysis
The following important HDP chains were detected:
* DIS # D1: 5,8 => CTR => D1: 9 * DIS # D3: 5,8 => CTR => D3: 4,9 * DIS # F2: 4 => CTR => F2: 7,8 * DIS # E8: 5,6 => CTR => E8: 7,8 * DIS # G2: 8 => CTR => G2: 2,3 * DIS # I3: 1,6 => CTR => I3: 8,9 * DIS # C3: 5,8 => CTR => C3: 4,7 * DIS # A6: 3,7 => CTR => A6: 4 * DIS # D1: 5,8 => CTR => D1: 9 * DIS # D3: 5,8 => CTR => D3: 4,9 * DIS # E8: 5,6 => CTR => E8: 7,8 * DIS # B7: 4,5 => CTR => B7: 2,3 * CNT 12 HDP CHAINS / 52 HYP OPENED
See Appendix: Full HDP Chains for full list of HDP chains.
Pair Reduction
The following important HDP chains were detected:
* DIS # D1: 5,8 => CTR => D1: 9 * DIS D1: 9 # D3: 5,8 => CTR => D3: 4 * PRF D1: 9 + D3: 4 # G3: 1,6 => SOL * STA D1: 9 + D3: 4 + G3: 1,6 * CNT 3 HDP CHAINS / 3 HYP OPENED
See Appendix: Full HDP Chains for full list of HDP chains.
Details
Positions
| ..2...47.1..6....5....32....6.7.3942.9..4......12........1...87.....9..4..6.2.59. | initial |
| ..2..147.1.96....5....32....6.71394229..4......129....9..1...87.....9..4..6.2.59. | autosolve |
| 632951478149687235857432169568713942293548716471296853924165387315879624786324591 | solved |
Classification
level: medium
Pairing Analysis
-------------------------------------------------- * PAIRS (11) E1: 5,8 E2: 7,8 H2: 2,3 H3: 1,6 A4: 5,8 C4: 5,8 C5: 3,7 D5: 5,8 E7: 5,6 F7: 4,5 I9: 1,3 -------------------------------------------------- * CONSTRAINT PAIRS (AUTO SOLVE) B8,B9: 1.. / B8 = 1 => 11 pairs (_) / B9 = 1 => 15 pairs (_) B9,I9: 1.. / B9 = 1 => 15 pairs (_) / I9 = 1 => 11 pairs (_) G2,H2: 2.. / G2 = 2 => 14 pairs (_) / H2 = 2 => 11 pairs (_) B7,B8: 2.. / B7 = 2 => 12 pairs (_) / B8 = 2 => 15 pairs (_) B7,G7: 2.. / B7 = 2 => 12 pairs (_) / G7 = 2 => 15 pairs (_) H2,H8: 2.. / H2 = 2 => 11 pairs (_) / H8 = 2 => 14 pairs (_) D8,D9: 3.. / D8 = 3 => 12 pairs (_) / D9 = 3 => 17 pairs (_) F2,D3: 4.. / F2 = 4 => 0 pairs (X) / D3 = 4 => 19 pairs (_) A6,B6: 4.. / A6 = 4 => 12 pairs (_) / B6 = 4 => 0 pairs (X) B2,F2: 4.. / B2 = 4 => 19 pairs (_) / F2 = 4 => 0 pairs (X) C3,C7: 4.. / C3 = 4 => 0 pairs (X) / C7 = 4 => 19 pairs (_) D3,D9: 4.. / D3 = 4 => 19 pairs (_) / D9 = 4 => 0 pairs (X) A4,C4: 5.. / A4 = 5 => 9 pairs (_) / C4 = 5 => 10 pairs (_) H5,H6: 5.. / H5 = 5 => 0 pairs (X) / H6 = 5 => 12 pairs (_) F6,H6: 5.. / F6 = 5 => 0 pairs (X) / H6 = 5 => 12 pairs (_) A1,A3: 6.. / A1 = 6 => 12 pairs (_) / A3 = 6 => 14 pairs (_) F5,F6: 6.. / F5 = 6 => 12 pairs (_) / F6 = 6 => 13 pairs (_) E7,E8: 6.. / E7 = 6 => 12 pairs (_) / E8 = 6 => 0 pairs (X) A1,I1: 6.. / A1 = 6 => 12 pairs (_) / I1 = 6 => 14 pairs (_) E7,G7: 6.. / E7 = 6 => 12 pairs (_) / G7 = 6 => 0 pairs (X) E2,F2: 7.. / E2 = 7 => 11 pairs (_) / F2 = 7 => 19 pairs (_) G5,G6: 7.. / G5 = 7 => 15 pairs (_) / G6 = 7 => 14 pairs (_) E8,F9: 7.. / E8 = 7 => 19 pairs (_) / F9 = 7 => 11 pairs (_) C5,G5: 7.. / C5 = 7 => 14 pairs (_) / G5 = 7 => 15 pairs (_) E2,E8: 7.. / E2 = 7 => 11 pairs (_) / E8 = 7 => 19 pairs (_) F2,F9: 7.. / F2 = 7 => 19 pairs (_) / F9 = 7 => 11 pairs (_) A4,C4: 8.. / A4 = 8 => 10 pairs (_) / C4 = 8 => 9 pairs (_) D1,D3: 9.. / D1 = 9 => 11 pairs (_) / D3 = 9 => 0 pairs (X) I1,I3: 9.. / I1 = 9 => 0 pairs (X) / I3 = 9 => 11 pairs (_) D1,I1: 9.. / D1 = 9 => 11 pairs (_) / I1 = 9 => 0 pairs (X) D3,I3: 9.. / D3 = 9 => 0 pairs (X) / I3 = 9 => 11 pairs (_) * DURATION: 0:00:30.627104 START: 19:55:44.637692 END: 19:56:15.264796 2019-04-30 * CP COUNT: (31) * CLUE FOUND -------------------------------------------------- * PREPARE PR GRAPH * PAIR REDUCTION .. * LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A4,C4,C5,D5,E1,E2,E7,F7,H2,H3,I9) * ..2..147.1.96....5....32....6.71394229..4......129....9..1...87.....9..4..6.2.59. * PAIR E1: 5,8 BLK 2 D1: 5,8,9 # reduction candidate for 5,8 D1: 5,8 => CTR * 632851479189674..5...932...56871394229.54....34129.75.92.165.87...389..4816427593 D1: 9 # 11 pairs D3: 5,8,4,9 # reduction candidate for 5,8 D3: 5,8 => CTR * ..295147.1.9674..5.57832..956871394229354.7..47129..5.94.165.877.5389..4..642759. D3: 4,9 # 13 pairs * PAIR E1: 5,8 ROW 1 A1: 5,8,3,6 # reduction candidate for 5,8 A1: 5,8 # 17 pairs B1: 5,8,3 # reduction candidate for 5,8 B1: 5,8 # 14 pairs * PAIR E1: 5,8 COL E E8: 5,8,6,7 # reduction candidate for 5,8 E8: 6,7 # 14 pairs E8: 5,8 # 13 pairs * PAIR E2: 7,8 BLK 2 F2: 7,8,4 # reduction candidate for 7,8 F2: 4 => CTR * 6.2.5147.1.9674..5.5..32....6871394229.54.....7129..5.943165.87...389..4..642759. F2: 7,8 # 19 pairs * PAIR E2: 7,8 COL E E8: 7,8,5,6 # reduction candidate for 7,8 E8: 5,6 => CTR * ..2.8147.1.9674..5....32....6.71394229..4......129....9..1.5.87....69..4..6.2759. E8: 7,8 # 14 pairs * PAIR H2: 2,3 BLK 3 G2: 2,3,8 # reduction candidate for 2,3 G2: 8 => CTR * 6.2951473139674825...832..9.6.71394229.54......129..5.9..165.87.1.389264386427591 G2: 2,3 # 13 pairs * PAIR H2: 2,3 COL H H8: 2,3,1,6 # reduction candidate for 2,3 H8: 1,6 # 15 pairs H8: 2,3 # 14 pairs * PAIR H3: 1,6 BLK 3 G3: 1,6,8 # reduction candidate for 1,6 G3: 1,6 # 15 pairs I3: 1,6,8,9 # reduction candidate for 1,6 I3: 1,6 => CTR * 632851479189674..5...9328..56871394229.54....34129.75.92.165.87...389..4816427593 I3: 8,9 # 12 pairs * PAIR H3: 1,6 COL H H5: 1,6,3,5 # reduction candidate for 1,6 H5: 1,6 # 15 pairs H8: 1,6,2,3 # reduction candidate for 1,6 H8: 1,6 # 15 pairs * PAIR A4: 5,8 COL A A1: 5,8,3,6 # reduction candidate for 5,8 A1: 5,8 # 17 pairs A3: 5,8,4,6,7 # reduction candidate for 5,8 A3: 5,8 # 14 pairs A8: 5,8,3,7 # reduction candidate for 5,8 A8: 5,8 # 13 pairs * PAIR C4: 5,8 COL C C3: 5,8,4,7 # reduction candidate for 5,8 C3: 5,8 => CTR * .32.5147.1496.7..5758432..986571394229.54....47129..5.9241653875173.9..4.86.2.591 C3: 4,7 # 12 pairs C8: 5,8,3,7 # reduction candidate for 5,8 C8: 5,8 # 14 pairs * PAIR C5: 3,7 BLK 4 A6: 3,7,4 # reduction candidate for 3,7 A6: 3,7 => CTR * 6.2.5147.1.9674..54...32....6.71394229354.7..74129..5.9.4165.875.7389..438642759. A6: 4 # 12 pairs B6: 3,7,4 # reduction candidate for 3,7 B6: 3,7 # 12 pairs * PAIR C5: 3,7 ROW 5 G5: 3,7,1,6,8 # reduction candidate for 3,7 G5: 1,6,8 # 14 pairs G5: 3,7 # 12 pairs * PAIR C5: 3,7 COL C C8: 3,7,5,8 # reduction candidate for 3,7 C8: 3,7 # 16 pairs C8: 5,8 # 14 pairs * PAIR D5: 5,8 BLK 5 F5: 5,8,6 # reduction candidate for 5,8 F5: 5,8 # 13 pairs F6: 5,8,6 # reduction candidate for 5,8 F6: 5,8 # 12 pairs * PAIR D5: 5,8 COL D D1: 5,8,9 # reduction candidate for 5,8 D1: 5,8 => CTR * 632851479189674..5...932...56871394229.54....34129.75.92.165.87...389..4816427593 D1: 9 # 11 pairs D3: 5,8,4,9 # reduction candidate for 5,8 D3: 5,8 => CTR * ..295147.1.9674..5.57832..956871394229354.7..47129..5.94.165.877.5389..4..642759. D3: 4,9 # 13 pairs D8: 5,8,3 # reduction candidate for 5,8 D8: 5,8 # 17 pairs * PAIR E7: 5,6 BLK 8 E8: 5,6,7,8 # reduction candidate for 5,6 E8: 5,6 => CTR * ..2.8147.1.9674..5....32....6.71394229..4......129....9..1.5.87....69..4..6.2759. E8: 7,8 # 14 pairs * PAIR F7: 4,5 ROW 7 B7: 4,5,2,3 # reduction candidate for 4,5 B7: 4,5 => CTR * ..2..147.189674325.74.32....6.713942297.4..3.43129.75.943165287725389..4816427593 B7: 2,3 # 12 pairs C7: 4,5,3 # reduction candidate for 4,5 C7: 4,5 # 14 pairs * PAIR I9: 1,3 BLK 9 G8: 1,3,2,6 # reduction candidate for 1,3 G8: 1,3 # 14 pairs H8: 1,3,2,6 # reduction candidate for 1,3 H8: 1,3 # 15 pairs * PAIR I9: 1,3 ROW 9 B9: 1,3,4,7,8 # reduction candidate for 1,3 B9: 1,3 # 13 pairs B9: 4,7,8 # 11 pairs * PAIR I9: 1,3 COL I I5: 1,3,6,8 # reduction candidate for 1,3 I5: 1,3 # 15 pairs I5: 6,8 # 14 pairs * INCONCLUSIVE * SAVE PR GRAPH zz-www.sudokuoftheday.co.uk-20060317-absurd-base-pr-000.dot * REASONING * DIS # D1: 5,8 => CTR => D1: 9 * DIS # D3: 5,8 => CTR => D3: 4,9 * DIS # F2: 4 => CTR => F2: 7,8 * DIS # E8: 5,6 => CTR => E8: 7,8 * DIS # G2: 8 => CTR => G2: 2,3 * DIS # I3: 1,6 => CTR => I3: 8,9 * DIS # C3: 5,8 => CTR => C3: 4,7 * DIS # A6: 3,7 => CTR => A6: 4 * DIS # D1: 5,8 => CTR => D1: 9 * DIS # D3: 5,8 => CTR => D3: 4,9 * DIS # E8: 5,6 => CTR => E8: 7,8 * DIS # B7: 4,5 => CTR => B7: 2,3 * CNT 12 HDP CHAINS / 52 HYP OPENED -------------------------------------------------- * PREPARE PR GRAPH * PAIR REDUCTION .. * LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A4,C4,C5,D5,E1,E2,E7,F7,H2,H3,I9) * ..2..147.1.96....5....32....6.71394229..4......129....9..1...87.....9..4..6.2.59. * PAIR E1: 5,8 BLK 2 D1: 5,8,9 # reduction candidate for 5,8 D1: 5,8 => CTR * 632851479189674..5...932...56871394229.54....34129.75.92.165.87...389..4816427593 D3: 5,8,4 # reduction candidate for 5,8 D3: 5,8 => CTR * ..295147.1.9674..5.57832..956871394229354.7..47129..5.94.165.877.5389..4..642759. * PAIR H3: 1,6 BLK 3 G3: 1,6,8 # reduction candidate for 1,6 G3: 1,6 => SOLVED * 632951478149687235857432169568713942293548716471296853924165387315879624786324591 * DURATION: 0:00:03.527174 START: 19:56:42.905584 END: 19:56:46.432758 2019-04-30 * SOLUTION FOUND * SAVE PR GRAPH zz-www.sudokuoftheday.co.uk-20060317-absurd-base-pr-001.dot * REASONING * DIS # D1: 5,8 => CTR => D1: 9 * DIS D1: 9 # D3: 5,8 => CTR => D3: 4 * PRF D1: 9 + D3: 4 # G3: 1,6 => SOL * STA D1: 9 + D3: 4 + G3: 1,6 * CNT 3 HDP CHAINS / 3 HYP OPENED
Header Info
http://www.sudokuoftheday.co.uk/cgi-bin/sudoku1280.cgi?ACTION=archive2&USER=&MONTH=Mar&YEAR=2006, 20060317, absurd
Solution
position: 632951478149687235857432169568713942293548716471296853924165387315879624786324591 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 # D1: 5,8 => CTR => D1: 9 * INC # D1: 9 => UNS * DIS # D3: 5,8 => CTR => D3: 4,9 * INC # D3: 4,9 => UNS * INC # A1: 5,8 => UNS * INC # B1: 5,8 => UNS * INC # E8: 5,8 => UNS * INC # E8: 6,7 => UNS * INC # F2: 7,8 => UNS * DIS # F2: 4 => CTR => F2: 7,8 * INC # E8: 7,8 => UNS * DIS # E8: 5,6 => CTR => E8: 7,8 * INC # G2: 2,3 => UNS * DIS # G2: 8 => CTR => G2: 2,3 * INC # H8: 2,3 => UNS * INC # H8: 1,6 => UNS * INC # G3: 1,6 => UNS * DIS # I3: 1,6 => CTR => I3: 8,9 * INC # I3: 8,9 => UNS * INC # H5: 1,6 => UNS * INC # H8: 1,6 => UNS * INC # A1: 5,8 => UNS * INC # A3: 5,8 => UNS * INC # A8: 5,8 => UNS * DIS # C3: 5,8 => CTR => C3: 4,7 * INC # C3: 4,7 => UNS * INC # C8: 5,8 => UNS * DIS # A6: 3,7 => CTR => A6: 4 * INC # A6: 4 => UNS * INC # B6: 3,7 => UNS * INC # G5: 3,7 => UNS * INC # G5: 1,6,8 => UNS * INC # C8: 3,7 => UNS * INC # C8: 5,8 => UNS * INC # F5: 5,8 => UNS * INC # F6: 5,8 => UNS * DIS # D1: 5,8 => CTR => D1: 9 * INC # D1: 9 => UNS * DIS # D3: 5,8 => CTR => D3: 4,9 * INC # D3: 4,9 => UNS * INC # D8: 5,8 => UNS * DIS # E8: 5,6 => CTR => E8: 7,8 * INC # E8: 7,8 => UNS * DIS # B7: 4,5 => CTR => B7: 2,3 * INC # B7: 2,3 => UNS * INC # C7: 4,5 => UNS * INC # G8: 1,3 => UNS * INC # H8: 1,3 => UNS * INC # B9: 1,3 => UNS * INC # B9: 4,7,8 => UNS * INC # I5: 1,3 => UNS * INC # I5: 6,8 => UNS * CNT 52 HDP CHAINS / 52 HYP OPENED
A2. Pair Reduction
Full list of HDP chains traversed:
* DIS # D1: 5,8 => CTR => D1: 9 * DIS D1: 9 # D3: 5,8 => CTR => D3: 4 * PRF D1: 9 + D3: 4 # G3: 1,6 => SOL * STA D1: 9 + D3: 4 + G3: 1,6 * CNT 3 HDP CHAINS / 3 HYP OPENED