Analysis of xx-top500-088-base.sdk

Contents

Original Sudoku

level: hard

Original Sudoku

position: ....5.1.3.2.6.........4.....8.2...6.......9......3.......7..24.3.1......5........ initial

Autosolve

position: 46.95.1.3.236.15.4.1534....18429536723.1.4958.5983.412.9.71324534152....5724.9.31 autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

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

Pair Reduction

Pair Reduction

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

Deep Pair Reduction

Deep Pair Reduction

Time used: 0:00:32.500596

The following important HDP chains were detected:

* DIS # A2: 7,8 # G8: 7,8 => CTR => G8: 6
* DIS # A2: 7,8 + G8: 6 => CTR => A2: 9
* PRF A2: 9 # H1: 7,8 => SOL
* STA A2: 9 + H1: 7,8
* CNT   3 HDP CHAINS /  26 HYP OPENED

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

Details

Positions

....5.1.3.2.6.........4.....8.2...6.......9......3.......7..24.3.1......5........ initial
46.95.1.3.236.15.4.1534....18429536723.1.4958.5983.412.9.71324534152....5724.9.31 autosolve
467952183923681574815347629184295367236174958759836412698713245341528796572469831 solved

Classification

level: hard

Pairing Analysis

--------------------------------------------------
* PAIRS (13)
C1: 7,8
E2: 7,8
I3: 6,9
C5: 6,7
A6: 6,7
E5: 6,7
F6: 6,7
A7: 6,8
C7: 6,8
F8: 6,8
E9: 6,8
I8: 6,9
G9: 6,8

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
F1,F3: 2.. / F1 = 2  => 15 pairs (_) / F3 = 2  => 14 pairs (_)
H1,H3: 2.. / H1 = 2  => 14 pairs (_) / H3 = 2  => 15 pairs (_)
F1,H1: 2.. / F1 = 2  => 15 pairs (_) / H1 = 2  => 14 pairs (_)
F3,H3: 2.. / F3 = 2  => 14 pairs (_) / H3 = 2  => 15 pairs (_)
G3,I3: 6.. / G3 = 6  =>  0 pairs (*) / I3 = 6  =>  0 pairs (X)
C5,A6: 6.. / C5 = 6  =>  0 pairs (*) / A6 = 6  =>  0 pairs (X)
E5,F6: 6.. / E5 = 6  =>  0 pairs (X) / F6 = 6  =>  0 pairs (_)
A7,C7: 6.. / A7 = 6  =>  0 pairs (*) / C7 = 6  =>  0 pairs (X)
F8,E9: 6.. / F8 = 6  =>  0 pairs (X) / E9 = 6  =>  0 pairs (_)
C5,E5: 6.. / C5 = 6  =>  0 pairs (*) / E5 = 6  =>  0 pairs (X)
A6,F6: 6.. / A6 = 6  =>  0 pairs (X) / F6 = 6  =>  0 pairs (_)
E9,G9: 6.. / E9 = 6  =>  0 pairs (*) / G9 = 6  =>  0 pairs (X)
A6,A7: 6.. / A6 = 6  =>  0 pairs (X) / A7 = 6  =>  0 pairs (_)
C5,C7: 6.. / C5 = 6  =>  0 pairs (*) / C7 = 6  =>  0 pairs (X)
E5,E9: 6.. / E5 = 6  =>  0 pairs (X) / E9 = 6  =>  0 pairs (_)
F6,F8: 6.. / F6 = 6  =>  0 pairs (*) / F8 = 6  =>  0 pairs (X)
I3,I8: 6.. / I3 = 6  => 13 pairs (_) / I8 = 6  =>  0 pairs (*)
C5,A6: 7.. / C5 = 7  =>  0 pairs (X) / A6 = 7  =>  0 pairs (_)
E5,F6: 7.. / E5 = 7  =>  0 pairs (*) / F6 = 7  =>  0 pairs (X)
G8,H8: 7.. / G8 = 7  => 15 pairs (_) / H8 = 7  => 16 pairs (_)
C5,E5: 7.. / C5 = 7  =>  0 pairs (X) / E5 = 7  =>  0 pairs (_)
A6,F6: 7.. / A6 = 7  =>  0 pairs (*) / F6 = 7  =>  0 pairs (X)
C1,C5: 7.. / C1 = 7  =>  0 pairs (*) / C5 = 7  =>  0 pairs (X)
E2,E5: 7.. / E2 = 7  =>  0 pairs (X) / E5 = 7  =>  0 pairs (_)
G3,G8: 7.. / G3 = 7  => 16 pairs (_) / G8 = 7  => 15 pairs (_)
A7,C7: 8.. / A7 = 8  =>  0 pairs (X) / C7 = 8  =>  0 pairs (_)
F8,E9: 8.. / F8 = 8  =>  0 pairs (*) / E9 = 8  =>  0 pairs (X)
E9,G9: 8.. / E9 = 8  =>  0 pairs (X) / G9 = 8  =>  0 pairs (_)
C1,C7: 8.. / C1 = 8  =>  0 pairs (X) / C7 = 8  =>  0 pairs (_)
E2,E9: 8.. / E2 = 8  =>  0 pairs (*) / E9 = 8  =>  0 pairs (X)
A2,A3: 9.. / A2 = 9  => 15 pairs (_) / A3 = 9  => 14 pairs (_)
H8,I8: 9.. / H8 = 9  =>  0 pairs (*) / I8 = 9  =>  0 pairs (X)
A2,H2: 9.. / A2 = 9  => 15 pairs (_) / H2 = 9  => 14 pairs (_)
I3,I8: 9.. / I3 = 9  =>  0 pairs (*) / I8 = 9  =>  0 pairs (X)
* DURATION: 0:01:07.653005  START: 05:46:48.859512  END: 05:47:56.512517 2017-05-04
* CP COUNT: (34)
* SOLUTION FOUND

* DEEP PAIR REDUCTION
* DURATION: 0:00:32.346677  START: 05:48:29.428984  END: 05:49:01.775661 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-088-base-pr-002.dot
* REASONING
* DIS # A2: 7,8 # G8: 7,8 => CTR => G8: 6
* DIS # A2: 7,8 + G8: 6 => CTR => A2: 9
* PRF A2: 9 # H1: 7,8 => SOL
* STA A2: 9 + H1: 7,8
* CNT   3 HDP CHAINS /  26 HYP OPENED

Header Info

Top 500 Minimum 17 088

solution: 467952183923681574815347629184295367236174958759836412698713245341528796572469831
info: 1560     FNBWXY   S8.f     4802

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

Solution

position: 467952183923681574815347629184295367236174958759836412698713245341528796572469831 solved
Solution

See section Deep Pair Reduction for the HDP chains leading to this result.

Appendix: Full HDP Chains

A1. Pair Reduction Analysis

Full list of HDP chains traversed:

* INC # A2: 7,8 => UNS
* INC # A3: 7,8 => UNS
* INC # F1: 7,8 => UNS
* INC # H1: 7,8 => UNS
* INC # F1: 7,8 => UNS
* INC # F3: 7,8 => UNS
* INC # A2: 7,8 => UNS
* INC # H2: 7,8 => UNS
* INC # G8: 6,8 => UNS
* INC # G8: 7 => UNS
* INC # G8: 6,8 => UNS
* INC # G8: 7 => UNS
* INC # G3: 6,8 => UNS
* INC # G3: 7 => UNS
* CNT  14 HDP CHAINS /  14 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* INC # A2: 7,8 => UNS
* INC # A3: 7,8 => UNS
* INC # F1: 7,8 => UNS
* INC # H1: 7,8 => UNS
* INC # F1: 7,8 => UNS
* INC # F3: 7,8 => UNS
* INC # A2: 7,8 => UNS
* INC # H2: 7,8 => UNS
* INC # G8: 6,8 => UNS
* INC # G8: 7 => UNS
* INC # G8: 6,8 => UNS
* INC # G8: 7 => UNS
* INC # G3: 6,8 => UNS
* INC # G3: 7 => UNS
* CNT  14 HDP CHAINS /  14 HYP OPENED

A3. Deep Pair Reduction

Full list of HDP chains traversed:

* INC # A2: 7,8 => UNS
* INC # A3: 7,8 => UNS
* INC # F1: 7,8 => UNS
* INC # H1: 7,8 => UNS
* INC # F1: 7,8 => UNS
* INC # F3: 7,8 => UNS
* INC # A2: 7,8 => UNS
* INC # H2: 7,8 => UNS
* INC # G8: 6,8 => UNS
* INC # G8: 7 => UNS
* INC # G8: 6,8 => UNS
* INC # G8: 7 => UNS
* INC # G3: 6,8 => UNS
* INC # G3: 7 => UNS
* INC # A2: 7,8 # F1: 7,8 => UNS
* INC # A2: 7,8 # H1: 7,8 => UNS
* INC # A2: 7,8 # F1: 7,8 => UNS
* INC # A2: 7,8 # F3: 7,8 => UNS
* INC # A2: 7,8 # H1: 7,8 => UNS
* INC # A2: 7,8 # H3: 7,8 => UNS
* INC # A2: 7,8 # F3: 7,8 => UNS
* INC # A2: 7,8 # F3: 2 => UNS
* DIS # A2: 7,8 # G8: 7,8 => CTR => G8: 6
* DIS # A2: 7,8 + G8: 6 => CTR => A2: 9
* INC A2: 9 # F1: 7,8 => UNS
* PRF A2: 9 # H1: 7,8 => SOL
* STA A2: 9 + H1: 7,8
* CNT  26 HDP CHAINS /  26 HYP OPENED