Analysis of xx-top500-001-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: .69..........4..3..8..........8..61.4.....9..5...2....2..9....5...6.1............ initial

Autosolve

position: .69.185..1..746839.84.9.1.69..8..61.4.8.6.95.5.6.29..82.198..658..6.129.69.....81 autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* PRF # D3: 2,3 => SOL
* DIS # D9: 2,3 => CTR => D9: 4,5
* DIS # H1: 2 => CTR => H1: 4,7
* DIS # I8: 4,7 => CTR => I8: 3
* DIS # H1: 2,7 => CTR => H1: 4
* DIS # D6: 1,3 => CTR => D6: 4
* PRF # D6: 4 => SOL
* DIS # E4: 3,7 => CTR => E4: 5
* PRF # E4: 5 => SOL
* PRF # F4: 3,7 => SOL
* DIS # I5: 3,7 => CTR => I5: 2
* DIS # F7: 3,7 => CTR => F7: 4
* PRF # F7: 4 => SOL
* DIS # F9: 3,7 => CTR => F9: 2,4,5
* DIS # G6: 4,7 => CTR => G6: 3
* DIS # H1: 2 => CTR => H1: 4,7
* CNT  16 HDP CHAINS /  32 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 # D3: 2,3 => SOL
* STA D3: 2,3
* CNT   1 HDP CHAINS /   1 HYP OPENED

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

Details

Positions

.69..........4..3..8..........8..61.4.....9..5...2....2..9....5...6.1............ initial
.69.185..1..746839.84.9.1.69..8..61.4.8.6.95.5.6.29..82.198..658..6.129.69.....81 autosolve
369218547152746839784395126923857614478163952516429378231984765845671293697532481 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (10)
A1: 3,7
B2: 2,5
C2: 2,5
A3: 3,7
D1: 2,3
I1: 4,7
H3: 2,7
D5: 1,3
F5: 3,7
H6: 4,7

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
B5,B6: 1.. / B5 = 1  =>  0 pairs (X) / B6 = 1  => 11 pairs (_)
D5,D6: 1.. / D5 = 1  => 11 pairs (_) / D6 = 1  =>  0 pairs (X)
B5,D5: 1.. / B5 = 1  =>  0 pairs (X) / D5 = 1  => 11 pairs (_)
B6,D6: 1.. / B6 = 1  => 11 pairs (_) / D6 = 1  =>  0 pairs (X)
B2,C2: 2.. / B2 = 2  =>  0 pairs (X) / C2 = 2  =>  9 pairs (_)
H1,H3: 2.. / H1 = 2  =>  0 pairs (X) / H3 = 2  =>  9 pairs (_)
I4,I5: 2.. / I4 = 2  =>  0 pairs (X) / I5 = 2  => 10 pairs (_)
D9,F9: 2.. / D9 = 2  =>  0 pairs (X) / F9 = 2  => 11 pairs (_)
D1,H1: 2.. / D1 = 2  =>  9 pairs (_) / H1 = 2  =>  0 pairs (X)
B5,I5: 2.. / B5 = 2  =>  0 pairs (X) / I5 = 2  => 10 pairs (_)
C2,C4: 2.. / C2 = 2  =>  9 pairs (_) / C4 = 2  =>  0 pairs (X)
F3,F9: 2.. / F3 = 2  =>  0 pairs (X) / F9 = 2  => 11 pairs (_)
A1,A3: 3.. / A1 = 3  =>  9 pairs (_) / A3 = 3  =>  0 pairs (X)
A1,D1: 3.. / A1 = 3  =>  9 pairs (_) / D1 = 3  =>  0 pairs (X)
H1,I1: 4.. / H1 = 4  => 10 pairs (_) / I1 = 4  =>  0 pairs (X)
F4,D6: 4.. / F4 = 4  =>  0 pairs (X) / D6 = 4  =>  0 pairs (_)
B7,B8: 4.. / B7 = 4  =>  0 pairs (X) / B8 = 4  => 12 pairs (_)
F4,I4: 4.. / F4 = 4  =>  0 pairs (X) / I4 = 4  =>  0 pairs (_)
B8,I8: 4.. / B8 = 4  => 12 pairs (_) / I8 = 4  =>  0 pairs (X)
D6,D9: 4.. / D6 = 4  =>  0 pairs (*) / D9 = 4  =>  0 pairs (X)
H1,H6: 4.. / H1 = 4  => 10 pairs (_) / H6 = 4  =>  0 pairs (X)
B2,C2: 5.. / B2 = 5  =>  9 pairs (_) / C2 = 5  =>  0 pairs (X)
D3,F3: 5.. / D3 = 5  => 11 pairs (_) / F3 = 5  =>  0 pairs (*)
E4,F4: 5.. / E4 = 5  =>  0 pairs (*) / F4 = 5  =>  0 pairs (X)
B2,B8: 5.. / B2 = 5  =>  9 pairs (_) / B8 = 5  =>  0 pairs (X)
D3,D9: 5.. / D3 = 5  => 11 pairs (_) / D9 = 5  =>  0 pairs (*)
A1,A3: 7.. / A1 = 7  =>  0 pairs (X) / A3 = 7  =>  9 pairs (_)
A3,H3: 7.. / A3 = 7  =>  9 pairs (_) / H3 = 7  =>  0 pairs (X)
* DURATION: 0:00:45.477027  START: 02:37:35.309447  END: 02:38:20.786474 2017-05-04
* CP COUNT: (28)
* SOLUTION FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A1,A3,B2,C2,D1,D5,F5,H3,H6,I1)
* .69.185..1..746839.84.9.1.69..8..61.4.8.6.95.5.6.29..82.198..658..6.129.69.....81
* PAIR D1: 2,3 BLK 2
D3: 2,3,5                                # reduction candidate for 2,3
D3: 2,3 => SOLVED
* 369218547152746839784395126923857614478163952516429378231984765845671293697532481
D3: 5                                    # 11 pairs
F3: 2,3,5                                # reduction candidate for 2,3
F3: 2,3                                  # 11 pairs
* PAIR D1: 2,3 COL D
D9: 2,3,4,5                              # reduction candidate for 2,3
D9: 2,3 => CTR
* .69.185471..7468397845931269..8..6144.816795251642937823198..658..6.129.69.....81
D9: 4,5                                  # 12 pairs
* PAIR I1: 4,7 BLK 3
H1: 4,7,2                                # reduction candidate for 4,7
H1: 2 => CTR
* .69.185241..746839.84.9.1769..8.461.4.8.6.95.5.6.29.482.198..6584.6.129.69.4.2.81
H1: 4,7                                  #  9 pairs
* PAIR I1: 4,7 COL I
I4: 4,7,2,3                              # reduction candidate for 4,7
I4: 4,7                                  # 17 pairs
I8: 4,7,3                                # reduction candidate for 4,7
I8: 4,7 => CTR
* 3692185..1..7468397845931269..8.461.4.8.6795.5.6.29..82.198..658..6.129.69.....81
I8: 3                                    # 17 pairs
* PAIR H3: 2,7 BLK 3
H1: 2,7,4                                # reduction candidate for 2,7
H1: 2,7 => CTR
* .69.185.4152746839.845931269..85461.4.8.6795.5.6.29.482.198..6584.6.129.69.4.2.81
H1: 4                                    # 10 pairs
* PAIR D5: 1,3 BLK 5
D6: 1,3,4                                # reduction candidate for 1,3
D6: 1,3 => CTR
* .69.185..1..746839.845931269..85461.4.8.6795.5.6.29..82.198..658..6.129.69.4.2.81
D6: 4 => SOLVED
* 369218547152746839784395126923857614478163952516429378231984765845671293697532481
* PAIR D5: 1,3 ROW 5
B5: 1,3,2,7                              # reduction candidate for 1,3
B5: 2,7                                  # 15 pairs
B5: 1,3                                  # 12 pairs
* PAIR F5: 3,7 BLK 5
E4: 3,7,5                                # reduction candidate for 3,7
E4: 3,7 => CTR
* .69.1854715274683978459312692.8.56144.81679525164293782.198..6584.6.129369.....81
E4: 5 => SOLVED
* 369218547152746839784395126923857614478163952516429378231984765845671293697532481
F4: 3,7,4,5                              # reduction candidate for 3,7
F4: 3,7 => SOLVED
* 369218547152746839784395126923857614478163952516429378231984765845671293697532481
F4: 4,5                                  # 11 pairs
* PAIR F5: 3,7 ROW 5
B5: 3,7,1,2                              # reduction candidate for 3,7
B5: 3,7                                  # 12 pairs
I5: 3,7,2                                # reduction candidate for 3,7
I5: 3,7 => CTR
* .69.185..152746839.84.9.1.69..8.461242816.95.516329..82.198..658..6.129.69.4.2.81
I5: 2                                    # 10 pairs
* PAIR F5: 3,7 COL F
F7: 3,7,4                                # reduction candidate for 3,7
F7: 3,7 => CTR
* .69.185..1..746839.845921769..8.56144.8.6.95.5.6.29..82.198..658..6.129.69.....81
F7: 4 => SOLVED
* 369218547152746839784395126923857614478163952516429378231984765845671293697532481
F9: 3,7,2,4,5                            # reduction candidate for 3,7
F9: 3,7 => CTR
* .69.185..1..746839.84.921769..8.56144.8.6.95.5.6.29..82.198..658..6.129.69.....81
F9: 2,4,5                                # 10 pairs
* PAIR H6: 4,7 BLK 6
I4: 4,7,2,3                              # reduction candidate for 4,7
I4: 4,7                                  # 17 pairs
G6: 4,7,3                                # reduction candidate for 4,7
G6: 4,7 => CTR
* 3692185..1..7468397845931269..8.461.4.8.6795.5.6.29..82.198..658..6.129.69.....81
G6: 3                                    # 17 pairs
* PAIR H6: 4,7 COL H
H1: 4,7,2                                # reduction candidate for 4,7
H1: 2 => CTR
* .69.185241..746839.84.9.1769..8.461.4.8.6.95.5.6.29.482.198..6584.6.129.69.4.2.81
H1: 4,7                                  #  9 pairs
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-001-base-pr-000.dot
* REASONING
* PRF # D3: 2,3 => SOL
* DIS # D9: 2,3 => CTR => D9: 4,5
* DIS # H1: 2 => CTR => H1: 4,7
* DIS # I8: 4,7 => CTR => I8: 3
* DIS # H1: 2,7 => CTR => H1: 4
* DIS # D6: 1,3 => CTR => D6: 4
* PRF # D6: 4 => SOL
* DIS # E4: 3,7 => CTR => E4: 5
* PRF # E4: 5 => SOL
* PRF # F4: 3,7 => SOL
* DIS # I5: 3,7 => CTR => I5: 2
* DIS # F7: 3,7 => CTR => F7: 4
* PRF # F7: 4 => SOL
* DIS # F9: 3,7 => CTR => F9: 2,4,5
* DIS # G6: 4,7 => CTR => G6: 3
* DIS # H1: 2 => CTR => H1: 4,7
* CNT  16 HDP CHAINS /  32 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A1,A3,B2,C2,D1,D5,F5,H3,H6,I1)
* .69.185..1..746839.84.9.1.69..8..61.4.8.6.95.5.6.29..82.198..658..6.129.69.....81
* PAIR D1: 2,3 BLK 2
D3: 2,3,5                                # reduction candidate for 2,3
D3: 2,3 => SOLVED
* 369218547152746839784395126923857614478163952516429378231984765845671293697532481
* DURATION: 0:00:02.294293  START: 02:38:50.613474  END: 02:38:52.907767 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-001-base-pr-001.dot
* REASONING
* PRF # D3: 2,3 => SOL
* STA D3: 2,3
* CNT   1 HDP CHAINS /   1 HYP OPENED

Header Info

Top 500 Minimum 17 001

solution: 369218547152746839784395126923857614478163952516429378231984765845671293697532481
info: 1305     FNBWY    S8.f     21983

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

Solution

position: 369218547152746839784395126923857614478163952516429378231984765845671293697532481 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 # D3: 2,3 => SOL
* INC # D3: 5 => UNS
* INC # F3: 2,3 => UNS
* DIS # D9: 2,3 => CTR => D9: 4,5
* INC # D9: 4,5 => UNS
* INC # H1: 4,7 => UNS
* DIS # H1: 2 => CTR => H1: 4,7
* INC # I4: 4,7 => UNS
* DIS # I8: 4,7 => CTR => I8: 3
* INC # I8: 3 => UNS
* DIS # H1: 2,7 => CTR => H1: 4
* INC # H1: 4 => UNS
* DIS # D6: 1,3 => CTR => D6: 4
* PRF # D6: 4 => SOL
* INC # B5: 1,3 => UNS
* INC # B5: 2,7 => UNS
* DIS # E4: 3,7 => CTR => E4: 5
* PRF # E4: 5 => SOL
* PRF # F4: 3,7 => SOL
* INC # F4: 4,5 => UNS
* INC # B5: 3,7 => UNS
* DIS # I5: 3,7 => CTR => I5: 2
* INC # I5: 2 => UNS
* DIS # F7: 3,7 => CTR => F7: 4
* PRF # F7: 4 => SOL
* DIS # F9: 3,7 => CTR => F9: 2,4,5
* INC # F9: 2,4,5 => UNS
* INC # I4: 4,7 => UNS
* DIS # G6: 4,7 => CTR => G6: 3
* INC # G6: 3 => UNS
* INC # H1: 4,7 => UNS
* DIS # H1: 2 => CTR => H1: 4,7
* CNT  32 HDP CHAINS /  32 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* PRF # D3: 2,3 => SOL
* STA D3: 2,3
* CNT   1 HDP CHAINS /   1 HYP OPENED