Analysis of xx-top500-033-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: ..26...3.4...7.................1.4.7.83............1.....3.2.6.75..........8..... initial

Autosolve

position: 8726...3.43..7...669..3..7.2695134871837246..547986123914352768758.6.3.23268.7... autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* PRF # F2: 1,5 => SOL
* DIS # H2: 1,5 => CTR => H2: 9
* PRF # H2: 9 => SOL
* DIS # F3: 1,5 => CTR => F3: 8
* PRF # I3: 1,5 => SOL
* DIS # I3: 4 => CTR => I3: 1,5
* PRF # I1: 4,9 => SOL
* DIS # I1: 1,5 => CTR => I1: 4,9
* DIS # D3: 1,2 => CTR => D3: 4
* PRF # D3: 4 => SOL
* DIS # I1: 5,9 => CTR => I1: 1,4
* PRF # H2: 5,9 => SOL
* DIS # H2: 1 => CTR => H2: 5,9
* DIS # F1: 5,9 => CTR => F1: 1
* PRF # F1: 1 => SOL
* PRF # H2: 5,9 => SOL
* DIS # H2: 1 => CTR => H2: 5,9
* DIS # H9: 5,9 => CTR => H9: 1,4
* DIS # I1: 5,9 => CTR => I1: 1,4
* PRF # I9: 5,9 => SOL
* DIS # I9: 1 => CTR => I9: 5,9
* DIS # D3: 2 => CTR => D3: 1,4
* PRF # F1: 1,9 => SOL
* DIS # F1: 5 => CTR => F1: 1,9
* DIS # F2: 1,9 => CTR => F2: 5,8
* PRF # F2: 5,8 => SOL
* DIS # H9: 4,9 => CTR => H9: 1,5
* PRF # H9: 1,5 => SOL
* DIS # H9: 4,9 => CTR => H9: 1,5
* PRF # H9: 1,5 => SOL
* DIS # H9: 5,9 => CTR => H9: 1,4
* PRF # I9: 5,9 => SOL
* DIS # I9: 1 => CTR => I9: 5,9
* CNT  33 HDP CHAINS /  40 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 # F2: 1,5 => SOL
* STA F2: 1,5
* CNT   1 HDP CHAINS /   1 HYP OPENED

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

Details

Positions

..26...3.4...7.................1.4.7.83............1.....3.2.6.75..........8..... initial
8726...3.43..7...669..3..7.2695134871837246..547986123914352768758.6.3.23268.7... autosolve
872691534431275896695438271269513487183724659547986123914352768758169342326847915 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (14)
C2: 1,5
C3: 1,5
E1: 4,9
D2: 1,2
G1: 5,9
G2: 2,8
G3: 2,8
H5: 5,9
I5: 5,9
D8: 1,4
F8: 1,9
E9: 4,9
H8: 4,9
G9: 5,9

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
C2,C3: 1.. / C2 = 1  =>  0 pairs (*) / C3 = 1  =>  0 pairs (X)
D8,F8: 1.. / D8 = 1  =>  0 pairs (*) / F8 = 1  =>  0 pairs (X)
H9,I9: 1.. / H9 = 1  =>  0 pairs (*) / I9 = 1  =>  0 pairs (X)
F1,I1: 1.. / F1 = 1  =>  0 pairs (*) / I1 = 1  =>  0 pairs (X)
H2,H9: 1.. / H2 = 1  =>  0 pairs (X) / H9 = 1  =>  0 pairs (_)
D2,D3: 2.. / D2 = 2  => 12 pairs (_) / D3 = 2  =>  0 pairs (X)
G2,G3: 2.. / G2 = 2  =>  0 pairs (X) / G3 = 2  => 12 pairs (_)
D2,G2: 2.. / D2 = 2  => 12 pairs (_) / G2 = 2  =>  0 pairs (X)
D3,G3: 2.. / D3 = 2  =>  0 pairs (X) / G3 = 2  => 12 pairs (_)
E1,D3: 4.. / E1 = 4  =>  0 pairs (X) / D3 = 4  =>  0 pairs (_)
I1,I3: 4.. / I1 = 4  =>  0 pairs (*) / I3 = 4  =>  0 pairs (X)
D8,E9: 4.. / D8 = 4  =>  0 pairs (X) / E9 = 4  =>  0 pairs (_)
H8,H9: 4.. / H8 = 4  =>  0 pairs (*) / H9 = 4  =>  0 pairs (X)
E1,I1: 4.. / E1 = 4  =>  0 pairs (X) / I1 = 4  =>  0 pairs (_)
D3,I3: 4.. / D3 = 4  =>  0 pairs (*) / I3 = 4  =>  0 pairs (X)
D8,H8: 4.. / D8 = 4  =>  0 pairs (X) / H8 = 4  =>  0 pairs (_)
E9,H9: 4.. / E9 = 4  =>  0 pairs (*) / H9 = 4  =>  0 pairs (X)
D3,D8: 4.. / D3 = 4  =>  0 pairs (*) / D8 = 4  =>  0 pairs (X)
E1,E9: 4.. / E1 = 4  =>  0 pairs (X) / E9 = 4  =>  0 pairs (_)
C2,C3: 5.. / C2 = 5  => 16 pairs (_) / C3 = 5  =>  0 pairs (*)
H5,I5: 5.. / H5 = 5  => 14 pairs (_) / I5 = 5  =>  0 pairs (X)
G1,G9: 5.. / G1 = 5  =>  0 pairs (*) / G9 = 5  =>  0 pairs (X)
F2,F3: 8.. / F2 = 8  =>  0 pairs (X) / F3 = 8  => 12 pairs (_)
G2,G3: 8.. / G2 = 8  => 12 pairs (_) / G3 = 8  =>  0 pairs (X)
F2,G2: 8.. / F2 = 8  =>  0 pairs (X) / G2 = 8  => 12 pairs (_)
F3,G3: 8.. / F3 = 8  => 12 pairs (_) / G3 = 8  =>  0 pairs (X)
H5,I5: 9.. / H5 = 9  =>  0 pairs (X) / I5 = 9  => 14 pairs (_)
F8,E9: 9.. / F8 = 9  =>  0 pairs (*) / E9 = 9  =>  0 pairs (X)
F2,H2: 9.. / F2 = 9  =>  0 pairs (X) / H2 = 9  =>  0 pairs (_)
F8,H8: 9.. / F8 = 9  =>  0 pairs (*) / H8 = 9  =>  0 pairs (X)
E1,E9: 9.. / E1 = 9  =>  0 pairs (*) / E9 = 9  =>  0 pairs (X)
G1,G9: 9.. / G1 = 9  =>  0 pairs (X) / G9 = 9  =>  0 pairs (_)
* DURATION: 0:01:21.361329  START: 03:47:12.484247  END: 03:48:33.845576 2017-05-04
* CP COUNT: (32)
* SOLUTION FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (C2,C3,D2,D8,E1,E9,F8,G1,G2,G3,G9,H5,H8,I5)
* 8726...3.43..7...669..3..7.2695134871837246..547986123914352768758.6.3.23268.7...
* PAIR C2: 1,5 ROW 2
F2: 1,5,8,9                              # reduction candidate for 1,5
F2: 1,5 => SOLVED
* 872691534431275896695438271269513487183724659547986123914352768758169342326847915
F2: 8,9                                  # 15 pairs
H2: 1,5,9                                # reduction candidate for 1,5
H2: 1,5 => CTR
* 8726...3.43..798.669..3827.2695134871837246..547986123914352768758.61392326897541
H2: 9 => SOLVED
* 872691534431275896695438271269513487183724659547986123914352768758169342326847915
* PAIR C3: 1,5 ROW 3
F3: 1,5,8                                # reduction candidate for 1,5
F3: 1,5 => CTR
* 8726...3.43..7829669.23.87426951348718372465954798612391435276875846.3.23268.7...
F3: 8                                    # 12 pairs
I3: 1,5,4                                # reduction candidate for 1,5
I3: 1,5 => SOLVED
* 872691534431275896695438271269513487183724659547986123914352768758169342326847915
I3: 4 => CTR
* 8726...3.43..7...669..3..742695134871837246..547986123914352768758461392326897541
* PAIR E1: 4,9 ROW 1
I1: 4,9,1,5                              # reduction candidate for 4,9
I1: 4,9 => SOLVED
* 872691534431275896695438271269513487183724659547986123914352768758169342326847915
I1: 1,5 => CTR
* 87264..3.43..7...669..3..742695134871837246..547986123914352768758461392326897541
* PAIR D2: 1,2 BLK 2
D3: 1,2,4                                # reduction candidate for 1,2
D3: 1,2 => CTR
* 87264..3.43..7...669..3..742695134871837246..547986123914352768758461392326897541
D3: 4 => SOLVED
* 872691534431275896695438271269513487183724659547986123914352768758169342326847915
* PAIR G1: 5,9 BLK 3
I1: 5,9,1,4                              # reduction candidate for 5,9
I1: 5,9 => CTR
* 872641.3.43.27...669..3..7.2695134871837246..547986123914352768758.6.3.23268.7...
I1: 1,4                                  # 15 pairs
H2: 5,9,1                                # reduction candidate for 5,9
H2: 5,9 => SOLVED
* 872691534431275896695438271269513487183724659547986123914352768758169342326847915
H2: 1 => CTR
* 8726...3.43..79816691.3827526951348718372465954798612391435276875816.3.23268.7...
* PAIR G1: 5,9 ROW 1
F1: 5,9,1                                # reduction candidate for 5,9
F1: 5,9 => CTR
* 8726...3143..7...669..3..742695134871837246..5479861239143527687584613923268.7...
F1: 1 => SOLVED
* 872691534431275896695438271269513487183724659547986123914352768758169342326847915
* PAIR H5: 5,9 COL H
H2: 5,9,1                                # reduction candidate for 5,9
H2: 5,9 => SOLVED
* 872691534431275896695438271269513487183724659547986123914352768758169342326847915
H2: 1 => CTR
* 8726...3.43..79816691.3827526951348718372465954798612391435276875816.3.23268.7...
H9: 5,9,1,4                              # reduction candidate for 5,9
H9: 5,9 => CTR
* 8726...3.43..7..16691.3..7.2695134871837246..547986123914352768758169342326847..1
H9: 1,4                                  # 15 pairs
* PAIR I5: 5,9 COL I
I1: 5,9,1,4                              # reduction candidate for 5,9
I1: 5,9 => CTR
* 872641.3.43.27...669..3..7.2695134871837246..547986123914352768758.6.3.23268.7...
I1: 1,4                                  # 15 pairs
I9: 5,9,1                                # reduction candidate for 5,9
I9: 5,9 => SOLVED
* 872691534431275896695438271269513487183724659547986123914352768758169342326847915
I9: 1 => CTR
* 8726.1.3.43.27.8166914382752695134871837246595479861239143527687581693.23268.7..1
* PAIR D8: 1,4 COL D
D3: 1,4,2                                # reduction candidate for 1,4
D3: 2 => CTR
* 87264..3.43..7...669.23.8742695134871837246..547986123914352768758461392326897541
D3: 1,4                                  # 12 pairs
* PAIR F8: 1,9 COL F
F1: 1,9,5                                # reduction candidate for 1,9
F1: 1,9 => SOLVED
* 872691534431275896695438271269513487183724659547986123914352768758169342326847915
F1: 5 => CTR
* 8726.593143..79856695.3827426951348718372469554798612391435276875846.3.23268.7...
F2: 1,9,5,8                              # reduction candidate for 1,9
F2: 1,9 => CTR
* 8726.593143.27985669513827426951348718372469554798612391435276875846.3.23268.7...
F2: 5,8 => SOLVED
* 872691534431275896695438271269513487183724659547986123914352768758169342326847915
* PAIR E9: 4,9 ROW 9
H9: 4,9,1,5                              # reduction candidate for 4,9
H9: 4,9 => CTR
* 8726...3.43..7..16691.3..7.269513487183724659547986123914352768758169342326847.91
H9: 1,5 => SOLVED
* 872691534431275896695438271269513487183724659547986123914352768758169342326847915
* PAIR H8: 4,9 BLK 9
H9: 4,9,1,5                              # reduction candidate for 4,9
H9: 4,9 => CTR
* 8726...3.43..7..16691.3..7.269513487183724659547986123914352768758169342326847.91
H9: 1,5 => SOLVED
* 872691534431275896695438271269513487183724659547986123914352768758169342326847915
* PAIR G9: 5,9 BLK 9
H9: 5,9,1,4                              # reduction candidate for 5,9
H9: 5,9 => CTR
* 8726...3.43..7..16691.3..7.2695134871837246..547986123914352768758169342326847..1
H9: 1,4                                  # 15 pairs
I9: 5,9,1                                # reduction candidate for 5,9
I9: 5,9 => SOLVED
* 872691534431275896695438271269513487183724659547986123914352768758169342326847915
I9: 1 => CTR
* 8726.1.3.43.27.8166914382752695134871837246595479861239143527687581693.23268.7..1
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-033-base-pr-000.dot
* REASONING
* PRF # F2: 1,5 => SOL
* DIS # H2: 1,5 => CTR => H2: 9
* PRF # H2: 9 => SOL
* DIS # F3: 1,5 => CTR => F3: 8
* PRF # I3: 1,5 => SOL
* DIS # I3: 4 => CTR => I3: 1,5
* PRF # I1: 4,9 => SOL
* DIS # I1: 1,5 => CTR => I1: 4,9
* DIS # D3: 1,2 => CTR => D3: 4
* PRF # D3: 4 => SOL
* DIS # I1: 5,9 => CTR => I1: 1,4
* PRF # H2: 5,9 => SOL
* DIS # H2: 1 => CTR => H2: 5,9
* DIS # F1: 5,9 => CTR => F1: 1
* PRF # F1: 1 => SOL
* PRF # H2: 5,9 => SOL
* DIS # H2: 1 => CTR => H2: 5,9
* DIS # H9: 5,9 => CTR => H9: 1,4
* DIS # I1: 5,9 => CTR => I1: 1,4
* PRF # I9: 5,9 => SOL
* DIS # I9: 1 => CTR => I9: 5,9
* DIS # D3: 2 => CTR => D3: 1,4
* PRF # F1: 1,9 => SOL
* DIS # F1: 5 => CTR => F1: 1,9
* DIS # F2: 1,9 => CTR => F2: 5,8
* PRF # F2: 5,8 => SOL
* DIS # H9: 4,9 => CTR => H9: 1,5
* PRF # H9: 1,5 => SOL
* DIS # H9: 4,9 => CTR => H9: 1,5
* PRF # H9: 1,5 => SOL
* DIS # H9: 5,9 => CTR => H9: 1,4
* PRF # I9: 5,9 => SOL
* DIS # I9: 1 => CTR => I9: 5,9
* CNT  33 HDP CHAINS /  40 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (C2,C3,D2,D8,E1,E9,F8,G1,G2,G3,G9,H5,H8,I5)
* 8726...3.43..7...669..3..7.2695134871837246..547986123914352768758.6.3.23268.7...
* PAIR C2: 1,5 ROW 2
F2: 1,5,8,9                              # reduction candidate for 1,5
F2: 1,5 => SOLVED
* 872691534431275896695438271269513487183724659547986123914352768758169342326847915
* DURATION: 0:00:02.529002  START: 03:49:39.650811  END: 03:49:42.179813 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-033-base-pr-001.dot
* REASONING
* PRF # F2: 1,5 => SOL
* STA F2: 1,5
* CNT   1 HDP CHAINS /   1 HYP OPENED

Header Info

Top 500 Minimum 17 033

solution: 872691534431275896695438271269513487183724659547986123914352768758169342326847915
info: 1338     FNBTWY   S8.f     13329

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

Solution

position: 872691534431275896695438271269513487183724659547986123914352768758169342326847915 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 # F2: 1,5 => SOL
* INC # F2: 8,9 => UNS
* DIS # H2: 1,5 => CTR => H2: 9
* PRF # H2: 9 => SOL
* DIS # F3: 1,5 => CTR => F3: 8
* INC # F3: 8 => UNS
* PRF # I3: 1,5 => SOL
* DIS # I3: 4 => CTR => I3: 1,5
* PRF # I1: 4,9 => SOL
* DIS # I1: 1,5 => CTR => I1: 4,9
* DIS # D3: 1,2 => CTR => D3: 4
* PRF # D3: 4 => SOL
* DIS # I1: 5,9 => CTR => I1: 1,4
* INC # I1: 1,4 => UNS
* PRF # H2: 5,9 => SOL
* DIS # H2: 1 => CTR => H2: 5,9
* DIS # F1: 5,9 => CTR => F1: 1
* PRF # F1: 1 => SOL
* PRF # H2: 5,9 => SOL
* DIS # H2: 1 => CTR => H2: 5,9
* DIS # H9: 5,9 => CTR => H9: 1,4
* INC # H9: 1,4 => UNS
* DIS # I1: 5,9 => CTR => I1: 1,4
* INC # I1: 1,4 => UNS
* PRF # I9: 5,9 => SOL
* DIS # I9: 1 => CTR => I9: 5,9
* INC # D3: 1,4 => UNS
* DIS # D3: 2 => CTR => D3: 1,4
* PRF # F1: 1,9 => SOL
* DIS # F1: 5 => CTR => F1: 1,9
* DIS # F2: 1,9 => CTR => F2: 5,8
* PRF # F2: 5,8 => SOL
* DIS # H9: 4,9 => CTR => H9: 1,5
* PRF # H9: 1,5 => SOL
* DIS # H9: 4,9 => CTR => H9: 1,5
* PRF # H9: 1,5 => SOL
* DIS # H9: 5,9 => CTR => H9: 1,4
* INC # H9: 1,4 => UNS
* PRF # I9: 5,9 => SOL
* DIS # I9: 1 => CTR => I9: 5,9
* CNT  40 HDP CHAINS /  40 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* PRF # F2: 1,5 => SOL
* STA F2: 1,5
* CNT   1 HDP CHAINS /   1 HYP OPENED