Analysis of xx-top500-454-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: ...76.2..4..8.....15............1.4..3....8...2..........2....37......1.....8.... initial

Autosolve

position: 3897642514.2815...15...24.88...21.4..314..82..24..81...1.24..83748..3.122.318.5.4 autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* DIS # H2: 6,7 => CTR => H2: 3,9
* PRF # B4: 9 => SOL
* DIS # C4: 5 => CTR => C4: 6,7
* DIS # H2: 6,7 => CTR => H2: 3,9
* PRF # H6: 6,7 => SOL
* DIS # F9: 6,9 => CTR => F9: 7
* PRF # A7: 9 => SOL
* DIS # C4: 5,6 => CTR => C4: 7
* DIS # A7: 5 => CTR => A7: 6,9
* DIS # F9: 6,9 => CTR => F9: 7
* DIS # B4: 7 => CTR => B4: 6,9
* DIS # G7: 6,9 => CTR => G7: 7
* CNT  12 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:

* DIS # H2: 6,7 => CTR => H2: 3,9
* PRF H2: 3,9 # B4: 9 => SOL
* STA H2: 3,9 + B4: 9
* CNT   2 HDP CHAINS /   5 HYP OPENED

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

Details

Positions

...76.2..4..8.....15............1.4..3....8...2..........2....37......1.....8.... initial
3897642514.2815...15...24.88...21.4..314..82..24..81...1.24..83748..3.122.318.5.4 autosolve
389764251472815936156932478897621345631459827524378169915246783748593612263187594 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (10)
B2: 6,7
C3: 6,7
D3: 3,9
E3: 3,9
H3: 6,7
F5: 6,9
C7: 5,6
B9: 6,9
E8: 5,9
G8: 6,9

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
D3,E3: 3.. / D3 = 3  =>  8 pairs (_) / E3 = 3  =>  9 pairs (_)
G2,H2: 3.. / G2 = 3  => 14 pairs (_) / H2 = 3  => 10 pairs (_)
G4,H6: 3.. / G4 = 3  => 10 pairs (_) / H6 = 3  => 14 pairs (_)
D4,G4: 3.. / D4 = 3  => 14 pairs (_) / G4 = 3  => 10 pairs (_)
E3,E6: 3.. / E3 = 3  =>  9 pairs (_) / E6 = 3  =>  8 pairs (_)
G2,G4: 3.. / G2 = 3  => 14 pairs (_) / G4 = 3  => 10 pairs (_)
H2,H6: 3.. / H2 = 3  => 10 pairs (_) / H6 = 3  => 14 pairs (_)
A7,C7: 5.. / A7 = 5  =>  0 pairs (X) / C7 = 5  => 11 pairs (_)
D8,E8: 5.. / D8 = 5  => 15 pairs (_) / E8 = 5  => 11 pairs (_)
C4,C7: 5.. / C4 = 5  =>  0 pairs (X) / C7 = 5  => 11 pairs (_)
B2,C3: 6.. / B2 = 6  =>  0 pairs (X) / C3 = 6  => 11 pairs (_)
C3,H3: 6.. / C3 = 6  => 11 pairs (_) / H3 = 6  =>  0 pairs (X)
D8,G8: 6.. / D8 = 6  => 17 pairs (_) / G8 = 6  => 16 pairs (_)
B2,C3: 7.. / B2 = 7  => 11 pairs (_) / C3 = 7  =>  0 pairs (X)
B4,C4: 7.. / B4 = 7  =>  0 pairs (X) / C4 = 7  => 11 pairs (_)
E5,E6: 7.. / E5 = 7  => 10 pairs (_) / E6 = 7  => 12 pairs (_)
F7,F9: 7.. / F7 = 7  =>  0 pairs (X) / F9 = 7  => 12 pairs (_)
G7,H9: 7.. / G7 = 7  => 12 pairs (_) / H9 = 7  =>  0 pairs (X)
C3,H3: 7.. / C3 = 7  =>  0 pairs (X) / H3 = 7  => 11 pairs (_)
E5,I5: 7.. / E5 = 7  => 10 pairs (_) / I5 = 7  => 12 pairs (_)
F7,G7: 7.. / F7 = 7  =>  0 pairs (X) / G7 = 7  => 12 pairs (_)
F9,H9: 7.. / F9 = 7  => 12 pairs (_) / H9 = 7  =>  0 pairs (X)
B2,B4: 7.. / B2 = 7  => 11 pairs (_) / B4 = 7  =>  0 pairs (X)
C3,C4: 7.. / C3 = 7  =>  0 pairs (X) / C4 = 7  => 11 pairs (_)
G2,G7: 7.. / G2 = 7  =>  0 pairs (X) / G7 = 7  => 12 pairs (_)
D3,E3: 9.. / D3 = 9  =>  9 pairs (_) / E3 = 9  =>  8 pairs (_)
A7,B9: 9.. / A7 = 9  =>  0 pairs (*) / B9 = 9  =>  0 pairs (X)
B4,B9: 9.. / B4 = 9  =>  0 pairs (*) / B9 = 9  =>  0 pairs (X)
* DURATION: 0:00:46.527441  START: 18:14:58.213080  END: 18:15:44.740521 2017-05-04
* CP COUNT: (28)
* SOLUTION FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (B2,B9,C3,C7,D3,E3,E8,F5,G8,H3)
* 3897642514.2815...15...24.88...21.4..314..82..24..81...1.24..83748..3.122.318.5.4
* PAIR B2: 6,7 ROW 2
G2: 6,7,3,9                              # reduction candidate for 6,7
G2: 6,7                                  # 14 pairs
H2: 6,7,3,9                              # reduction candidate for 6,7
H2: 6,7 => CTR
* 3897642514.28153.915.9324.889732164..314..82..24..813..1.24.783748..3.122.3187594
H2: 3,9                                  # 11 pairs
I2: 6,7,9                                # reduction candidate for 6,7
I2: 6,7                                  # 16 pairs
* PAIR B2: 6,7 COL B
B4: 6,7,9                                # reduction candidate for 6,7
B4: 9 => SOLVED
* 389764251472815936156932478897621345631459827524378169915246783748593612263187594
B4: 6,7                                  # 19 pairs
* PAIR C3: 6,7 COL C
C4: 6,7,5                                # reduction candidate for 6,7
C4: 5 => CTR
* 389764251462815739157..2468875.213466314.982..24..81..51624..83748..3612293186574
C4: 6,7                                  # 11 pairs
* PAIR D3: 3,9 COL D
D4: 3,9,5,6                              # reduction candidate for 3,9
D4: 3,9                                  # 13 pairs
D6: 3,9,5,6                              # reduction candidate for 3,9
D6: 3,9                                  # 13 pairs
* PAIR E3: 3,9 COL E
E6: 3,9,5,7                              # reduction candidate for 3,9
E6: 5,7                                  # 11 pairs
E6: 3,9                                  # 11 pairs
* PAIR H3: 6,7 BLK 3
G2: 6,7,3,9                              # reduction candidate for 6,7
G2: 6,7                                  # 14 pairs
H2: 6,7,3,9                              # reduction candidate for 6,7
H2: 6,7 => CTR
* 3897642514.28153.915.9324.889732164..314..82..24..813..1.24.783748..3.122.3187594
H2: 3,9                                  # 11 pairs
I2: 6,7,9                                # reduction candidate for 6,7
I2: 6,7                                  # 16 pairs
* PAIR H3: 6,7 COL H
H6: 6,7,3,9                              # reduction candidate for 6,7
H6: 6,7 => SOLVED
* 389764251472815936156932478897621345631459827524378169915246783748593612263187594
H6: 3,9                                  # 12 pairs
H9: 6,7,9                                # reduction candidate for 6,7
H9: 6,7                                  # 15 pairs
* PAIR F5: 6,9 BLK 5
D4: 6,9,3,5                              # reduction candidate for 6,9
D4: 6,9                                  # 13 pairs
D6: 6,9,3,5                              # reduction candidate for 6,9
D6: 6,9                                  # 13 pairs
* PAIR F5: 6,9 ROW 5
A5: 6,9,5                                # reduction candidate for 6,9
A5: 6,9                                  # 13 pairs
I5: 6,9,5,7                              # reduction candidate for 6,9
I5: 6,9                                  # 13 pairs
* PAIR F5: 6,9 COL F
F7: 6,9,7                                # reduction candidate for 6,9
F7: 6,9                                  # 12 pairs
F9: 6,9,7                                # reduction candidate for 6,9
F9: 6,9 => CTR
* 389764251462815739157..246887.92134..314..82..24..819..1.247.83748..3.12293186574
F9: 7                                    # 12 pairs
* PAIR C7: 5,6 BLK 7
A7: 5,6,9                                # reduction candidate for 5,6
A7: 9 => SOLVED
* 389764251472815936156932478897621345631459827524378169915246783748593612263187594
A7: 5,6                                  # 19 pairs
* PAIR C7: 5,6 COL C
C4: 5,6,7                                # reduction candidate for 5,6
C4: 5,6 => CTR
* 389764251462815739157..246887..2134..314.982.924..81...1.24..83748..3.12293186574
C4: 7                                    # 11 pairs
* PAIR B9: 6,9 BLK 7
A7: 6,9,5                                # reduction candidate for 6,9
A7: 5 => CTR
* 389764251462815739157..2468875.213466314.982..24..81..51624..83748..3612293186574
A7: 6,9                                  # 11 pairs
* PAIR B9: 6,9 ROW 9
F9: 6,9,7                                # reduction candidate for 6,9
F9: 6,9 => CTR
* 389764251462815739157..246887.92134..314..82..24..819..1.247.83748..3.12293186574
F9: 7                                    # 12 pairs
H9: 6,9,7                                # reduction candidate for 6,9
H9: 6,9                                  # 12 pairs
* PAIR B9: 6,9 COL B
B4: 6,9,7                                # reduction candidate for 6,9
B4: 7 => CTR
* 389764251462815739157..246887..2134..314.982.924..81...1.24..83748..3.12293186574
B4: 6,9                                  # 11 pairs
* PAIR E8: 5,9 BLK 8
D8: 5,9,6                                # reduction candidate for 5,9
D8: 6                                    # 17 pairs
D8: 5,9                                  # 16 pairs
* PAIR E8: 5,9 COL E
E5: 5,9,7                                # reduction candidate for 5,9
E5: 5,9                                  # 12 pairs
E6: 5,9,3,7                              # reduction candidate for 5,9
E6: 5,9                                  # 10 pairs
* PAIR G8: 6,9 BLK 9
G7: 6,9,7                                # reduction candidate for 6,9
G7: 6,9 => CTR
* 389764251462815739157..246887.92134..314..82..24..819..1.247.83748..3.12293186574
G7: 7                                    # 12 pairs
H9: 6,9,7                                # reduction candidate for 6,9
H9: 6,9                                  # 12 pairs
* PAIR G8: 6,9 ROW 8
D8: 6,9,5                                # reduction candidate for 6,9
D8: 5                                    # 15 pairs
D8: 6,9                                  # 11 pairs
* PAIR G8: 6,9 COL G
G2: 6,9,3,7                              # reduction candidate for 6,9
G2: 6,9                                  # 13 pairs
G4: 6,9,3                                # reduction candidate for 6,9
G4: 6,9                                  # 14 pairs
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-454-base-pr-000.dot
* REASONING
* DIS # H2: 6,7 => CTR => H2: 3,9
* PRF # B4: 9 => SOL
* DIS # C4: 5 => CTR => C4: 6,7
* DIS # H2: 6,7 => CTR => H2: 3,9
* PRF # H6: 6,7 => SOL
* DIS # F9: 6,9 => CTR => F9: 7
* PRF # A7: 9 => SOL
* DIS # C4: 5,6 => CTR => C4: 7
* DIS # A7: 5 => CTR => A7: 6,9
* DIS # F9: 6,9 => CTR => F9: 7
* DIS # B4: 7 => CTR => B4: 6,9
* DIS # G7: 6,9 => CTR => G7: 7
* CNT  12 HDP CHAINS /  48 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (B2,B9,C3,C7,D3,E3,E8,F5,G8,H3)
* 3897642514.2815...15...24.88...21.4..314..82..24..81...1.24..83748..3.122.318.5.4
* PAIR B2: 6,7 ROW 2
G2: 6,7,3,9                              # reduction candidate for 6,7
G2: 6,7                                  # 14 pairs
H2: 6,7,3,9                              # reduction candidate for 6,7
H2: 6,7 => CTR
* 3897642514.28153.915.9324.889732164..314..82..24..813..1.24.783748..3.122.3187594
I2: 6,7,9                                # reduction candidate for 6,7
I2: 6,7                                  # 16 pairs
* PAIR B2: 6,7 COL B
B4: 6,7,9                                # reduction candidate for 6,7
B4: 9 => SOLVED
* 389764251472815936156932478897621345631459827524378169915246783748593612263187594
* DURATION: 0:00:05.904511  START: 18:16:29.416502  END: 18:16:35.321013 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-454-base-pr-001.dot
* REASONING
* DIS # H2: 6,7 => CTR => H2: 3,9
* PRF H2: 3,9 # B4: 9 => SOL
* STA H2: 3,9 + B4: 9
* CNT   2 HDP CHAINS /   5 HYP OPENED

Header Info

Top 500 Minimum 17 454

solution: 389764251472815936156932478897621345631459827524378169915246783748593612263187594
info: 95477    FNBXK    S8.f     11908

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

Solution

position: 389764251472815936156932478897621345631459827524378169915246783748593612263187594 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:

* INC # G2: 6,7 => UNS
* DIS # H2: 6,7 => CTR => H2: 3,9
* INC # H2: 3,9 => UNS
* INC # I2: 6,7 => UNS
* INC # B4: 6,7 => UNS
* PRF # B4: 9 => SOL
* INC # C4: 6,7 => UNS
* DIS # C4: 5 => CTR => C4: 6,7
* INC # D4: 3,9 => UNS
* INC # D6: 3,9 => UNS
* INC # E6: 3,9 => UNS
* INC # E6: 5,7 => UNS
* INC # G2: 6,7 => UNS
* DIS # H2: 6,7 => CTR => H2: 3,9
* INC # H2: 3,9 => UNS
* INC # I2: 6,7 => UNS
* PRF # H6: 6,7 => SOL
* INC # H6: 3,9 => UNS
* INC # H9: 6,7 => UNS
* INC # D4: 6,9 => UNS
* INC # D6: 6,9 => UNS
* INC # A5: 6,9 => UNS
* INC # I5: 6,9 => UNS
* INC # F7: 6,9 => UNS
* DIS # F9: 6,9 => CTR => F9: 7
* INC # F9: 7 => UNS
* INC # A7: 5,6 => UNS
* PRF # A7: 9 => SOL
* DIS # C4: 5,6 => CTR => C4: 7
* INC # C4: 7 => UNS
* INC # A7: 6,9 => UNS
* DIS # A7: 5 => CTR => A7: 6,9
* DIS # F9: 6,9 => CTR => F9: 7
* INC # F9: 7 => UNS
* INC # H9: 6,9 => UNS
* INC # B4: 6,9 => UNS
* DIS # B4: 7 => CTR => B4: 6,9
* INC # D8: 5,9 => UNS
* INC # D8: 6 => UNS
* INC # E5: 5,9 => UNS
* INC # E6: 5,9 => UNS
* DIS # G7: 6,9 => CTR => G7: 7
* INC # G7: 7 => UNS
* INC # H9: 6,9 => UNS
* INC # D8: 6,9 => UNS
* INC # D8: 5 => UNS
* INC # G2: 6,9 => UNS
* INC # G4: 6,9 => UNS
* CNT  48 HDP CHAINS /  48 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* INC # G2: 6,7 => UNS
* DIS # H2: 6,7 => CTR => H2: 3,9
* INC H2: 3,9 # I2: 6,7 => UNS
* INC H2: 3,9 # B4: 6,7 => UNS
* PRF H2: 3,9 # B4: 9 => SOL
* STA H2: 3,9 + B4: 9
* CNT   5 HDP CHAINS /   5 HYP OPENED