Analysis of xx-top500-102-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: ..6.83....1....2...........8.3....5....1..4..........674.2........4..1.........8. initial

Autosolve

position: 426.83.17.18...263.376..84.863....512..1364.81.48..3267412.863.38.46.1.26.23...84 autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* PRF # D2: 5,9 => SOL
* DIS # D2: 7 => CTR => D2: 5,9
* PRF # D2: 5,9 => SOL
* DIS # D2: 7 => CTR => D2: 5,9
* DIS # G9: 5,9 => CTR => G9: 7
* PRF # G9: 7 => SOL
* PRF # B5: 5,9 => SOL
* DIS # B5: 7 => CTR => B5: 5,9
* DIS # B5: 7,9 => CTR => B5: 5
* PRF # B5: 5 => SOL
* DIS # E6: 7,9 => CTR => E6: 5
* PRF # E6: 5 => SOL
* PRF # F6: 7,9 => SOL
* DIS # F6: 5 => CTR => F6: 7,9
* DIS # E6: 7,9 => CTR => E6: 5
* PRF # E6: 5 => SOL
* PRF # F6: 7,9 => SOL
* DIS # F6: 5 => CTR => F6: 7,9
* DIS # D2: 7,9 => CTR => D2: 5
* PRF # D2: 5 => SOL
* PRF # G9: 7,9 => SOL
* DIS # G9: 5 => CTR => G9: 7,9
* DIS # B5: 7,9 => CTR => B5: 5
* PRF # B5: 5 => SOL
* DIS # F8: 5,9 => CTR => F8: 7
* PRF # F8: 7 => SOL
* DIS # E9: 5,9 => CTR => E9: 1,7
* PRF # F9: 5,9 => SOL
* DIS # G9: 5,9 => CTR => G9: 7
* PRF # G9: 7 => SOL
* PRF # B5: 5,9 => SOL
* DIS # B5: 7 => CTR => B5: 5,9
* DIS # F8: 5,9 => CTR => F8: 7
* PRF # F8: 7 => SOL
* DIS # E9: 5,9 => CTR => E9: 1,7
* PRF # F9: 5,9 => SOL
* DIS # E6: 7 => CTR => E6: 5,9
* DIS # G9: 5,9 => CTR => G9: 7
* PRF # G9: 7 => SOL
* PRF # G9: 7,9 => SOL
* DIS # G9: 5 => CTR => G9: 7,9
* PRF # F8: 7,9 => SOL
* DIS # F8: 5 => CTR => F8: 7,9
* CNT  43 HDP CHAINS /  48 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 # D2: 5,9 => SOL
* STA D2: 5,9
* CNT   1 HDP CHAINS /   1 HYP OPENED

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

Details

Positions

..6.83....1....2...........8.3....5....1..4..........674.2........4..1.........8. initial
426.83.17.18...263.376..84.863....512..1364.81.48..3267412.863.38.46.1.26.23...84 autosolve
426983517918574263537621849863742951259136478174859326741298635385467192692315784 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (19)
A2: 5,9
A3: 5,9
D1: 5,9
E3: 1,2
F3: 1,2
G1: 5,9
I3: 5,9
C5: 5,9
B6: 7,9
D4: 7,9
E4: 2,4
F4: 2,4
G4: 7,9
H5: 7,9
C8: 5,9
B9: 5,9
E7: 5,9
I7: 5,9
H8: 7,9

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
E3,F3: 1.. / E3 = 1  => 16 pairs (_) / F3 = 1  => 17 pairs (_)
E9,F9: 1.. / E9 = 1  => 17 pairs (_) / F9 = 1  => 16 pairs (_)
E3,E9: 1.. / E3 = 1  => 16 pairs (_) / E9 = 1  => 17 pairs (_)
F3,F9: 1.. / F3 = 1  => 17 pairs (_) / F9 = 1  => 16 pairs (_)
E3,F3: 2.. / E3 = 2  => 17 pairs (_) / F3 = 2  => 16 pairs (_)
E4,F4: 2.. / E4 = 2  => 16 pairs (_) / F4 = 2  => 17 pairs (_)
E3,E4: 2.. / E3 = 2  => 17 pairs (_) / E4 = 2  => 16 pairs (_)
F3,F4: 2.. / F3 = 2  => 16 pairs (_) / F4 = 2  => 17 pairs (_)
E2,F2: 4.. / E2 = 4  => 16 pairs (_) / F2 = 4  => 17 pairs (_)
E4,F4: 4.. / E4 = 4  => 17 pairs (_) / F4 = 4  => 16 pairs (_)
E2,E4: 4.. / E2 = 4  => 16 pairs (_) / E4 = 4  => 17 pairs (_)
F2,F4: 4.. / F2 = 4  => 17 pairs (_) / F4 = 4  => 16 pairs (_)
A2,A3: 5.. / A2 = 5  =>  0 pairs (X) / A3 = 5  =>  0 pairs (_)
D1,D2: 5.. / D1 = 5  =>  0 pairs (X) / D2 = 5  =>  0 pairs (_)
G1,I3: 5.. / G1 = 5  =>  0 pairs (*) / I3 = 5  =>  0 pairs (X)
B5,C5: 5.. / B5 = 5  =>  0 pairs (*) / C5 = 5  =>  0 pairs (X)
E6,F6: 5.. / E6 = 5  =>  0 pairs (*) / F6 = 5  =>  0 pairs (X)
C8,B9: 5.. / C8 = 5  =>  0 pairs (*) / B9 = 5  =>  0 pairs (X)
I7,G9: 5.. / I7 = 5  =>  0 pairs (*) / G9 = 5  =>  0 pairs (X)
D1,G1: 5.. / D1 = 5  =>  0 pairs (X) / G1 = 5  =>  0 pairs (_)
A2,D2: 5.. / A2 = 5  =>  0 pairs (X) / D2 = 5  =>  0 pairs (_)
A3,I3: 5.. / A3 = 5  =>  0 pairs (*) / I3 = 5  =>  0 pairs (X)
E7,I7: 5.. / E7 = 5  =>  0 pairs (X) / I7 = 5  =>  0 pairs (_)
C8,F8: 5.. / C8 = 5  =>  0 pairs (*) / F8 = 5  =>  0 pairs (X)
B5,B9: 5.. / B5 = 5  =>  0 pairs (*) / B9 = 5  =>  0 pairs (X)
C5,C8: 5.. / C5 = 5  =>  0 pairs (X) / C8 = 5  =>  0 pairs (_)
G1,G9: 5.. / G1 = 5  =>  0 pairs (*) / G9 = 5  =>  0 pairs (X)
I3,I7: 5.. / I3 = 5  =>  0 pairs (X) / I7 = 5  =>  0 pairs (_)
B5,B6: 7.. / B5 = 7  =>  0 pairs (X) / B6 = 7  =>  0 pairs (_)
G4,H5: 7.. / G4 = 7  =>  0 pairs (X) / H5 = 7  =>  0 pairs (_)
H8,G9: 7.. / H8 = 7  =>  0 pairs (X) / G9 = 7  =>  0 pairs (_)
D4,G4: 7.. / D4 = 7  =>  0 pairs (*) / G4 = 7  =>  0 pairs (X)
B5,H5: 7.. / B5 = 7  =>  0 pairs (X) / H5 = 7  =>  0 pairs (_)
F8,H8: 7.. / F8 = 7  =>  0 pairs (*) / H8 = 7  =>  0 pairs (X)
D2,D4: 7.. / D2 = 7  =>  0 pairs (X) / D4 = 7  =>  0 pairs (_)
G4,G9: 7.. / G4 = 7  =>  0 pairs (X) / G9 = 7  =>  0 pairs (_)
H5,H8: 7.. / H5 = 7  =>  0 pairs (*) / H8 = 7  =>  0 pairs (X)
A2,A3: 9.. / A2 = 9  =>  0 pairs (*) / A3 = 9  =>  0 pairs (X)
G1,I3: 9.. / G1 = 9  =>  0 pairs (X) / I3 = 9  =>  0 pairs (_)
G4,H5: 9.. / G4 = 9  =>  0 pairs (*) / H5 = 9  =>  0 pairs (X)
C8,B9: 9.. / C8 = 9  =>  0 pairs (X) / B9 = 9  =>  0 pairs (_)
D1,G1: 9.. / D1 = 9  =>  0 pairs (*) / G1 = 9  =>  0 pairs (X)
A3,I3: 9.. / A3 = 9  =>  0 pairs (X) / I3 = 9  =>  0 pairs (_)
D4,G4: 9.. / D4 = 9  =>  0 pairs (X) / G4 = 9  =>  0 pairs (_)
E7,I7: 9.. / E7 = 9  =>  0 pairs (*) / I7 = 9  =>  0 pairs (X)
C5,C8: 9.. / C5 = 9  =>  0 pairs (*) / C8 = 9  =>  0 pairs (X)
H5,H8: 9.. / H5 = 9  =>  0 pairs (X) / H8 = 9  =>  0 pairs (_)
I3,I7: 9.. / I3 = 9  =>  0 pairs (*) / I7 = 9  =>  0 pairs (X)
* DURATION: 0:01:57.442236  START: 06:14:19.371371  END: 06:16:16.813607 2017-05-04
* CP COUNT: (48)
* SOLUTION FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A2,A3,B6,B9,C5,C8,D1,D4,E3,E4,E7,F3,F4,G1,G4,H5,H8,I3,I7)
* 426.83.17.18...263.376..84.863....512..1364.81.48..3267412.863.38.46.1.26.23...84
* PAIR A2: 5,9 ROW 2
D2: 5,9,7                                # reduction candidate for 5,9
D2: 5,9 => SOLVED
* 426983517918574263537621849863742951259136478174859326741298635385467192692315784
D2: 7 => CTR
* 4265839175187..2639376..8458639..7512751364981948..3267412586393894671.26.23...84
* PAIR D1: 5,9 BLK 2
D2: 5,9,7                                # reduction candidate for 5,9
D2: 5,9 => SOLVED
* 426983517918574263537621849863742951259136478174859326741298635385467192692315784
D2: 7 => CTR
* 4265839175187..2639376..8458639..7512751364981948..3267412586393894671.26.23...84
* PAIR G1: 5,9 COL G
G9: 5,9,7                                # reduction candidate for 5,9
G9: 5,9 => CTR
* 426983.17.18...263.376..84.863...7512751364981948..3267412.863.3894651726523..984
G9: 7 => SOLVED
* 426983517918574263537621849863742951259136478174859326741298635385467192692315784
* PAIR C5: 5,9 BLK 4
B5: 5,9,7                                # reduction candidate for 5,9
B5: 5,9 => SOLVED
* 426983517918574263537621849863742951259136478174859326741298635385467192692315784
B5: 7 => CTR
* 4269835179185..2635376..8498637...512751364981948..3267412.863.3894651726523..984
* PAIR B6: 7,9 BLK 4
B5: 7,9,5                                # reduction candidate for 7,9
B5: 7,9 => CTR
* 4269835179185..2635376..8498637...512.51364.81.48..3267412.863.3894651726523..984
B5: 5 => SOLVED
* 426983517918574263537621849863742951259136478174859326741298635385467192692315784
* PAIR B6: 7,9 ROW 6
E6: 7,9,5                                # reduction candidate for 7,9
E6: 7,9 => CTR
* 426.83.17.18...263.376..84.863....5125913647817489532674125863.38546.1.26923...84
E6: 5 => SOLVED
* 426983517918574263537621849863742951259136478174859326741298635385467192692315784
F6: 7,9,5                                # reduction candidate for 7,9
F6: 7,9 => SOLVED
* 426983517918574263537621849863742951259136478174859326741298635385467192692315784
F6: 5 => CTR
* 426.83.17.18...263.376..84.863....5125913647817489532674125863.38546.1.26923...84
* PAIR D4: 7,9 BLK 5
E6: 7,9,5                                # reduction candidate for 7,9
E6: 7,9 => CTR
* 426.83.17.18...263.376..84.863....5125913647817489532674125863.38546.1.26923...84
E6: 5 => SOLVED
* 426983517918574263537621849863742951259136478174859326741298635385467192692315784
F6: 7,9,5                                # reduction candidate for 7,9
F6: 7,9 => SOLVED
* 426983517918574263537621849863742951259136478174859326741298635385467192692315784
F6: 5 => CTR
* 426.83.17.18...263.376..84.863....5125913647817489532674125863.38546.1.26923...84
* PAIR D4: 7,9 COL D
D2: 7,9,5                                # reduction candidate for 7,9
D2: 7,9 => CTR
* 426583917518...2639376..8458639..7512751364981948..3267412586393894671.26.23...84
D2: 5 => SOLVED
* 426983517918574263537621849863742951259136478174859326741298635385467192692315784
* PAIR G4: 7,9 COL G
G9: 7,9,5                                # reduction candidate for 7,9
G9: 7,9 => SOLVED
* 426983517918574263537621849863742951259136478174859326741298635385467192692315784
G9: 5 => CTR
* 426.83.17.18...263.376..84.863...7512751364981948..3267412.86393894651.26.23...84
* PAIR H5: 7,9 ROW 5
B5: 7,9,5                                # reduction candidate for 7,9
B5: 7,9 => CTR
* 4269835179185..2635376..8498637...512.51364.81.48..3267412.863.3894651726523..984
B5: 5 => SOLVED
* 426983517918574263537621849863742951259136478174859326741298635385467192692315784
* PAIR C8: 5,9 ROW 8
F8: 5,9,7                                # reduction candidate for 5,9
F8: 5,9 => CTR
* 426983.17.18...263.376..84.863...7512751364981948..3267412.863.3894651726523..984
F8: 7 => SOLVED
* 426983517918574263537621849863742951259136478174859326741298635385467192692315784
* PAIR B9: 5,9 ROW 9
E9: 5,9,1,7                              # reduction candidate for 5,9
E9: 5,9 => CTR
* 426.83517.185472635376128498637249512..1364781748..32674129863538.4651.26.23.1784
E9: 1,7                                  # 20 pairs
F9: 5,9,1,7                              # reduction candidate for 5,9
F9: 5,9 => SOLVED
* 426983517918574263537621849863742951259136478174859326741298635385467192692315784
F9: 1,7                                  # 20 pairs
G9: 5,9,7                                # reduction candidate for 5,9
G9: 5,9 => CTR
* 426983.17.18...263.376..84.863...7512751364981948..3267412.863.3894651726523..984
G9: 7 => SOLVED
* 426983517918574263537621849863742951259136478174859326741298635385467192692315784
* PAIR B9: 5,9 COL B
B5: 5,9,7                                # reduction candidate for 5,9
B5: 5,9 => SOLVED
* 426983517918574263537621849863742951259136478174859326741298635385467192692315784
B5: 7 => CTR
* 4269835179185..2635376..8498637...512751364981948..3267412.863.3894651726523..984
* PAIR E7: 5,9 BLK 8
F8: 5,9,7                                # reduction candidate for 5,9
F8: 5,9 => CTR
* 426983.17.18...263.376..84.863...7512751364981948..3267412.863.3894651726523..984
F8: 7 => SOLVED
* 426983517918574263537621849863742951259136478174859326741298635385467192692315784
E9: 5,9,1,7                              # reduction candidate for 5,9
E9: 5,9 => CTR
* 426.83517.185472635376128498637249512..1364781748..32674129863538.4651.26.23.1784
E9: 1,7                                  # 20 pairs
F9: 5,9,1,7                              # reduction candidate for 5,9
F9: 5,9 => SOLVED
* 426983517918574263537621849863742951259136478174859326741298635385467192692315784
F9: 1,7                                  # 20 pairs
* PAIR E7: 5,9 COL E
E6: 5,9,7                                # reduction candidate for 5,9
E6: 7 => CTR
* 426.83.17.18...263.376..84.863....512..1364.81.48753267412.863.38546.1.26923...84
E6: 5,9                                  # 22 pairs
* PAIR I7: 5,9 BLK 9
G9: 5,9,7                                # reduction candidate for 5,9
G9: 5,9 => CTR
* 426983.17.18...263.376..84.863...7512751364981948..3267412.863.3894651726523..984
G9: 7 => SOLVED
* 426983517918574263537621849863742951259136478174859326741298635385467192692315784
* PAIR H8: 7,9 BLK 9
G9: 7,9,5                                # reduction candidate for 7,9
G9: 7,9 => SOLVED
* 426983517918574263537621849863742951259136478174859326741298635385467192692315784
G9: 5 => CTR
* 426.83.17.18...263.376..84.863...7512751364981948..3267412.86393894651.26.23...84
* PAIR H8: 7,9 ROW 8
F8: 7,9,5                                # reduction candidate for 7,9
F8: 7,9 => SOLVED
* 426983517918574263537621849863742951259136478174859326741298635385467192692315784
F8: 5 => CTR
* 4269835179185..2635376..8498637...512..1364.81.48..3267412.863.38.4651726523..984
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-102-base-pr-000.dot
* REASONING
* PRF # D2: 5,9 => SOL
* DIS # D2: 7 => CTR => D2: 5,9
* PRF # D2: 5,9 => SOL
* DIS # D2: 7 => CTR => D2: 5,9
* DIS # G9: 5,9 => CTR => G9: 7
* PRF # G9: 7 => SOL
* PRF # B5: 5,9 => SOL
* DIS # B5: 7 => CTR => B5: 5,9
* DIS # B5: 7,9 => CTR => B5: 5
* PRF # B5: 5 => SOL
* DIS # E6: 7,9 => CTR => E6: 5
* PRF # E6: 5 => SOL
* PRF # F6: 7,9 => SOL
* DIS # F6: 5 => CTR => F6: 7,9
* DIS # E6: 7,9 => CTR => E6: 5
* PRF # E6: 5 => SOL
* PRF # F6: 7,9 => SOL
* DIS # F6: 5 => CTR => F6: 7,9
* DIS # D2: 7,9 => CTR => D2: 5
* PRF # D2: 5 => SOL
* PRF # G9: 7,9 => SOL
* DIS # G9: 5 => CTR => G9: 7,9
* DIS # B5: 7,9 => CTR => B5: 5
* PRF # B5: 5 => SOL
* DIS # F8: 5,9 => CTR => F8: 7
* PRF # F8: 7 => SOL
* DIS # E9: 5,9 => CTR => E9: 1,7
* PRF # F9: 5,9 => SOL
* DIS # G9: 5,9 => CTR => G9: 7
* PRF # G9: 7 => SOL
* PRF # B5: 5,9 => SOL
* DIS # B5: 7 => CTR => B5: 5,9
* DIS # F8: 5,9 => CTR => F8: 7
* PRF # F8: 7 => SOL
* DIS # E9: 5,9 => CTR => E9: 1,7
* PRF # F9: 5,9 => SOL
* DIS # E6: 7 => CTR => E6: 5,9
* DIS # G9: 5,9 => CTR => G9: 7
* PRF # G9: 7 => SOL
* PRF # G9: 7,9 => SOL
* DIS # G9: 5 => CTR => G9: 7,9
* PRF # F8: 7,9 => SOL
* DIS # F8: 5 => CTR => F8: 7,9
* CNT  43 HDP CHAINS /  48 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A2,A3,B6,B9,C5,C8,D1,D4,E3,E4,E7,F3,F4,G1,G4,H5,H8,I3,I7)
* 426.83.17.18...263.376..84.863....512..1364.81.48..3267412.863.38.46.1.26.23...84
* PAIR A2: 5,9 ROW 2
D2: 5,9,7                                # reduction candidate for 5,9
D2: 5,9 => SOLVED
* 426983517918574263537621849863742951259136478174859326741298635385467192692315784
* DURATION: 0:00:02.514649  START: 06:17:31.295147  END: 06:17:33.809796 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-102-base-pr-001.dot
* REASONING
* PRF # D2: 5,9 => SOL
* STA D2: 5,9
* CNT   1 HDP CHAINS /   1 HYP OPENED

Header Info

Top 500 Minimum 17 102

solution: 426983517918574263537621849863742951259136478174859326741298635385467192692315784
info: 1595     FNBTWXY  S8.f     14106

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

Solution

position: 426983517918574263537621849863742951259136478174859326741298635385467192692315784 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 # D2: 5,9 => SOL
* DIS # D2: 7 => CTR => D2: 5,9
* PRF # D2: 5,9 => SOL
* DIS # D2: 7 => CTR => D2: 5,9
* DIS # G9: 5,9 => CTR => G9: 7
* PRF # G9: 7 => SOL
* PRF # B5: 5,9 => SOL
* DIS # B5: 7 => CTR => B5: 5,9
* DIS # B5: 7,9 => CTR => B5: 5
* PRF # B5: 5 => SOL
* DIS # E6: 7,9 => CTR => E6: 5
* PRF # E6: 5 => SOL
* PRF # F6: 7,9 => SOL
* DIS # F6: 5 => CTR => F6: 7,9
* DIS # E6: 7,9 => CTR => E6: 5
* PRF # E6: 5 => SOL
* PRF # F6: 7,9 => SOL
* DIS # F6: 5 => CTR => F6: 7,9
* DIS # D2: 7,9 => CTR => D2: 5
* PRF # D2: 5 => SOL
* PRF # G9: 7,9 => SOL
* DIS # G9: 5 => CTR => G9: 7,9
* DIS # B5: 7,9 => CTR => B5: 5
* PRF # B5: 5 => SOL
* DIS # F8: 5,9 => CTR => F8: 7
* PRF # F8: 7 => SOL
* DIS # E9: 5,9 => CTR => E9: 1,7
* INC # E9: 1,7 => UNS
* PRF # F9: 5,9 => SOL
* INC # F9: 1,7 => UNS
* DIS # G9: 5,9 => CTR => G9: 7
* PRF # G9: 7 => SOL
* PRF # B5: 5,9 => SOL
* DIS # B5: 7 => CTR => B5: 5,9
* DIS # F8: 5,9 => CTR => F8: 7
* PRF # F8: 7 => SOL
* DIS # E9: 5,9 => CTR => E9: 1,7
* INC # E9: 1,7 => UNS
* PRF # F9: 5,9 => SOL
* INC # F9: 1,7 => UNS
* INC # E6: 5,9 => UNS
* DIS # E6: 7 => CTR => E6: 5,9
* DIS # G9: 5,9 => CTR => G9: 7
* PRF # G9: 7 => SOL
* PRF # G9: 7,9 => SOL
* DIS # G9: 5 => CTR => G9: 7,9
* PRF # F8: 7,9 => SOL
* DIS # F8: 5 => CTR => F8: 7,9
* CNT  48 HDP CHAINS /  48 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* PRF # D2: 5,9 => SOL
* STA D2: 5,9
* CNT   1 HDP CHAINS /   1 HYP OPENED