Analysis of xx-top500-244-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: ....7.8.......84..3.........5.....311......7.....4......86..2...2.3........1..... initial

Autosolve

position: 41.2738..2.7.184.338.4..1278547.2.311.283..74.73.41.827386.421..2138.74..4.1273.8 autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* PRF # C1: 6,9 => SOL
* DIS # C1: 5 => CTR => C1: 6,9
* PRF # H2: 6,9 => SOL
* DIS # H2: 5 => CTR => H2: 6,9
* DIS # C1: 6 => CTR => C1: 5,9
* DIS # F3: 5,9 => CTR => F3: 6
* DIS # F3: 5,9 => CTR => F3: 6
* DIS # H2: 6 => CTR => H2: 5,9
* DIS # F5: 6,9 => CTR => F5: 5
* PRF # F5: 5 => SOL
* PRF # G5: 6,9 => SOL
* DIS # G5: 5 => CTR => G5: 6,9
* DIS # G6: 6,9 => CTR => G6: 5
* PRF # G6: 5 => SOL
* PRF # A9: 6,9 => SOL
* DIS # F5: 6,9 => CTR => F5: 5
* PRF # F5: 5 => SOL
* DIS # E3: 5 => CTR => E3: 6,9
* DIS # F5: 6 => CTR => F5: 5,9
* DIS # G6: 6 => CTR => G6: 5,9
* PRF # G5: 6,9 => SOL
* DIS # G5: 5 => CTR => G5: 6,9
* DIS # G6: 6,9 => CTR => G6: 5
* PRF # G6: 5 => SOL
* PRF # A9: 6,9 => SOL
* PRF # H9: 5 => SOL
* PRF # C1: 6,9 => SOL
* DIS # C1: 5 => CTR => C1: 6,9
* DIS # E3: 6 => CTR => E3: 5,9
* DIS # I8: 5,9 => CTR => I8: 6
* DIS # F3: 5,9 => CTR => F3: 6
* DIS # I8: 5,9 => CTR => I8: 6
* DIS # I1: 6 => CTR => I1: 5,9
* CNT  33 HDP CHAINS /  55 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 # C1: 6,9 => SOL
* STA C1: 6,9
* CNT   1 HDP CHAINS /   1 HYP OPENED

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

Details

Positions

....7.8.......84..3.........5.....311......7.....4......86..2...2.3........1..... initial
41.2738..2.7.184.338.4..1278547.2.311.283..74.73.41.827386.421..2138.74..4.1273.8 autosolve
419273865267518493385496127854762931192835674673941582738654219521389746946127358 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (12)
B2: 6,9
C3: 5,9
D2: 5,9
B5: 6,9
A6: 6,9
E4: 6,9
D6: 5,9
G4: 6,9
C9: 6,9
E7: 5,9
F8: 5,9
I7: 5,9

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
C1,C3: 5.. / C1 = 5  =>  0 pairs (X) / C3 = 5  =>  0 pairs (_)
F5,D6: 5.. / F5 = 5  =>  0 pairs (*) / D6 = 5  =>  0 pairs (X)
G5,G6: 5.. / G5 = 5  =>  0 pairs (X) / G6 = 5  =>  0 pairs (_)
A8,A9: 5.. / A8 = 5  =>  0 pairs (*) / A9 = 5  =>  0 pairs (X)
E7,F8: 5.. / E7 = 5  => 16 pairs (_) / F8 = 5  =>  0 pairs (X)
D2,H2: 5.. / D2 = 5  =>  0 pairs (*) / H2 = 5  =>  0 pairs (X)
F5,G5: 5.. / F5 = 5  =>  0 pairs (*) / G5 = 5  =>  0 pairs (X)
D6,G6: 5.. / D6 = 5  =>  0 pairs (X) / G6 = 5  =>  0 pairs (_)
E7,I7: 5.. / E7 = 5  => 16 pairs (_) / I7 = 5  =>  0 pairs (X)
A9,H9: 5.. / A9 = 5  => 15 pairs (_) / H9 = 5  =>  0 pairs (*)
D2,D6: 5.. / D2 = 5  =>  0 pairs (*) / D6 = 5  =>  0 pairs (X)
E3,E7: 5.. / E3 = 5  =>  0 pairs (X) / E7 = 5  => 16 pairs (_)
C1,B2: 6.. / C1 = 6  =>  0 pairs (X) / B2 = 6  => 17 pairs (_)
E3,F3: 6.. / E3 = 6  =>  0 pairs (X) / F3 = 6  => 14 pairs (_)
B5,A6: 6.. / B5 = 6  =>  0 pairs (X) / A6 = 6  => 17 pairs (_)
E4,F5: 6.. / E4 = 6  => 14 pairs (_) / F5 = 6  =>  0 pairs (X)
I8,H9: 6.. / I8 = 6  => 15 pairs (_) / H9 = 6  =>  0 pairs (X)
B2,H2: 6.. / B2 = 6  => 17 pairs (_) / H2 = 6  =>  0 pairs (X)
E4,G4: 6.. / E4 = 6  => 14 pairs (_) / G4 = 6  =>  0 pairs (X)
A6,G6: 6.. / A6 = 6  => 17 pairs (_) / G6 = 6  =>  0 pairs (X)
A8,I8: 6.. / A8 = 6  =>  0 pairs (X) / I8 = 6  => 15 pairs (_)
B2,B5: 6.. / B2 = 6  => 17 pairs (_) / B5 = 6  =>  0 pairs (X)
C1,C9: 6.. / C1 = 6  =>  0 pairs (X) / C9 = 6  => 17 pairs (_)
E3,E4: 6.. / E3 = 6  =>  0 pairs (X) / E4 = 6  => 14 pairs (_)
F3,F5: 6.. / F3 = 6  => 14 pairs (_) / F5 = 6  =>  0 pairs (X)
I1,I8: 6.. / I1 = 6  =>  0 pairs (X) / I8 = 6  => 15 pairs (_)
B5,A6: 9.. / B5 = 9  => 17 pairs (_) / A6 = 9  =>  0 pairs (X)
E7,F8: 9.. / E7 = 9  =>  0 pairs (X) / F8 = 9  => 16 pairs (_)
E4,G4: 9.. / E4 = 9  =>  0 pairs (X) / G4 = 9  => 14 pairs (_)
E7,I7: 9.. / E7 = 9  =>  0 pairs (X) / I7 = 9  => 16 pairs (_)
B2,B5: 9.. / B2 = 9  =>  0 pairs (X) / B5 = 9  => 17 pairs (_)
D2,D6: 9.. / D2 = 9  =>  0 pairs (X) / D6 = 9  =>  0 pairs (_)
* DURATION: 0:00:56.150772  START: 11:08:13.008855  END: 11:09:09.159627 2017-05-04
* CP COUNT: (32)
* SOLUTION FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A6,B2,B5,C3,C9,D2,D6,E4,E7,F8,G4,I7)
* 41.2738..2.7.184.338.4..1278547.2.311.283..74.73.41.827386.421..2138.74..4.1273.8
* PAIR B2: 6,9 BLK 1
C1: 6,9,5                                # reduction candidate for 6,9
C1: 6,9 => SOLVED
* 419273865267518493385496127854762931192835674673941582738654219521389746946127358
C1: 5 => CTR
* 4152738..267.184533894..1278547.2.3119283..746735419827386.421..21389746.4.1273.8
* PAIR B2: 6,9 ROW 2
H2: 6,9,5                                # reduction candidate for 6,9
H2: 6,9 => SOLVED
* 419273865267518493385496127854762931192835674673941582738654219521389746946127358
H2: 5 => CTR
* 41.2738..2679184533894..1278547.2.3119283..746735419827386.421..21389746.4.1273.8
* PAIR C3: 5,9 BLK 1
C1: 5,9,6                                # reduction candidate for 5,9
C1: 6 => CTR
* 4162738..2975184633854..1278547.2.31162835974.73.41.827386.421..2138.74..4.1273.8
C1: 5,9                                  # 17 pairs
* PAIR C3: 5,9 ROW 3
E3: 5,9,6                                # reduction candidate for 5,9
E3: 5,9                                  # 14 pairs
F3: 5,9,6                                # reduction candidate for 5,9
F3: 5,9 => CTR
* 41.2738..2.7.184.338.46.1278547926311.2836574673541982738654219.21389746946127358
F3: 6                                    # 14 pairs
* PAIR D2: 5,9 BLK 2
E3: 5,9,6                                # reduction candidate for 5,9
E3: 5,9                                  # 14 pairs
F3: 5,9,6                                # reduction candidate for 5,9
F3: 5,9 => CTR
* 41.2738..2.7.184.338.46.1278547926311.2836574673541982738654219.21389746946127358
F3: 6                                    # 14 pairs
* PAIR D2: 5,9 ROW 2
H2: 5,9,6                                # reduction candidate for 5,9
H2: 6 => CTR
* 41.2738..2.75184633854..1278547.2.31162835974.73.41.827386.421..2138.74..4.1273.8
H2: 5,9                                  # 17 pairs
* PAIR B5: 6,9 ROW 5
F5: 6,9,5                                # reduction candidate for 6,9
F5: 6,9 => CTR
* 41.2738..2.79184533894..1278547.2.311928365746735419827386.421..21389746.4.1273.8
F5: 5 => SOLVED
* 419273865267518493385496127854762931192835674673941582738654219521389746946127358
G5: 6,9,5                                # reduction candidate for 6,9
G5: 6,9 => SOLVED
* 419273865267518493385496127854762931192835674673941582738654219521389746946127358
G5: 5 => CTR
* 41.2738..2.79184533894..1278547.2.311928365746735419827386.421..21389746.4.1273.8
* PAIR A6: 6,9 ROW 6
G6: 6,9,5                                # reduction candidate for 6,9
G6: 6,9 => CTR
* 41.2738..2.79184533894..1278547.2.311928365746735419827386.421..21389746.4.1273.8
G6: 5 => SOLVED
* 419273865267518493385496127854762931192835674673941582738654219521389746946127358
* PAIR A6: 6,9 COL A
A8: 6,9,5                                # reduction candidate for 6,9
A8: 6,9                                  # 15 pairs
A9: 6,9,5                                # reduction candidate for 6,9
A9: 6,9 => SOLVED
* 419273865267518493385496127854762931192835674673941582738654219521389746946127358
A9: 5                                    # 15 pairs
* PAIR E4: 6,9 BLK 5
F5: 6,9,5                                # reduction candidate for 6,9
F5: 6,9 => CTR
* 41.2738..2.79184533894..1278547.2.311928365746735419827386.421..21389746.4.1273.8
F5: 5 => SOLVED
* 419273865267518493385496127854762931192835674673941582738654219521389746946127358
* PAIR E4: 6,9 COL E
E3: 6,9,5                                # reduction candidate for 6,9
E3: 5 => CTR
* 4152738..26791845338945612785476293119283..74.73541682738694215.2138574.54.1273.8
E3: 6,9                                  # 16 pairs
* PAIR D6: 5,9 BLK 5
F5: 5,9,6                                # reduction candidate for 5,9
F5: 6 => CTR
* 41.27386.26791845338946512785479263119283657467354198273865421..2138.746.461273.8
F5: 5,9                                  # 14 pairs
* PAIR D6: 5,9 ROW 6
G6: 5,9,6                                # reduction candidate for 5,9
G6: 6 => CTR
* 41.2738..2.79184533894..1278547629311.283.574.735416827386.421..2138.74..4.1273.8
G6: 5,9                                  # 17 pairs
* PAIR G4: 6,9 BLK 6
G5: 6,9,5                                # reduction candidate for 6,9
G5: 6,9 => SOLVED
* 419273865267518493385496127854762931192835674673941582738654219521389746946127358
G5: 5 => CTR
* 41.2738..2.79184533894..1278547.2.311928365746735419827386.421..21389746.4.1273.8
G6: 6,9,5                                # reduction candidate for 6,9
G6: 6,9 => CTR
* 41.2738..2.79184533894..1278547.2.311928365746735419827386.421..21389746.4.1273.8
G6: 5 => SOLVED
* 419273865267518493385496127854762931192835674673941582738654219521389746946127358
* PAIR C9: 6,9 BLK 7
A8: 6,9,5                                # reduction candidate for 6,9
A8: 6,9                                  # 15 pairs
A9: 6,9,5                                # reduction candidate for 6,9
A9: 6,9 => SOLVED
* 419273865267518493385496127854762931192835674673941582738654219521389746946127358
A9: 5                                    # 15 pairs
* PAIR C9: 6,9 ROW 9
H9: 6,9,5                                # reduction candidate for 6,9
H9: 5 => SOLVED
* 419273865267518493385496127854762931192835674673941582738654219521389746946127358
H9: 6,9                                  # 15 pairs
* PAIR C9: 6,9 COL C
C1: 6,9,5                                # reduction candidate for 6,9
C1: 6,9 => SOLVED
* 419273865267518493385496127854762931192835674673941582738654219521389746946127358
C1: 5 => CTR
* 4152738..267.184533894..1278547.2.3119283..746735419827386.421..21389746.4.1273.8
* PAIR E7: 5,9 COL E
E3: 5,9,6                                # reduction candidate for 5,9
E3: 6 => CTR
* 41.2738..2.7.184.338.46.1278547926311.2836574673541982738654219.21389746946127358
E3: 5,9                                  # 14 pairs
* PAIR F8: 5,9 ROW 8
A8: 5,9,6                                # reduction candidate for 5,9
A8: 5,9                                  # 15 pairs
I8: 5,9,6                                # reduction candidate for 5,9
I8: 5,9 => CTR
* 41.2738.6267.184.338.4..1278547.2.3119283..74673.41.827386.421..2138.74..461273.8
I8: 6                                    # 15 pairs
* PAIR F8: 5,9 COL F
F3: 5,9,6                                # reduction candidate for 5,9
F3: 5,9 => CTR
* 41.2738..2.7.184.338.46.1278547926311.2836574673541982738654219.21389746946127358
F3: 6                                    # 14 pairs
F5: 5,9,6                                # reduction candidate for 5,9
F5: 5,9                                  # 14 pairs
* PAIR I7: 5,9 BLK 9
I8: 5,9,6                                # reduction candidate for 5,9
I8: 5,9 => CTR
* 41.2738.6267.184.338.4..1278547.2.3119283..74673.41.827386.421..2138.74..461273.8
I8: 6                                    # 15 pairs
H9: 5,9,6                                # reduction candidate for 5,9
H9: 5,9                                  # 15 pairs
* PAIR I7: 5,9 COL I
I1: 5,9,6                                # reduction candidate for 5,9
I1: 6 => CTR
* 41.2738.6267.184.338.4..1278547.2.3119283..74673.41.827386.421..2138.74..461273.8
I1: 5,9                                  # 15 pairs
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-244-base-pr-000.dot
* REASONING
* PRF # C1: 6,9 => SOL
* DIS # C1: 5 => CTR => C1: 6,9
* PRF # H2: 6,9 => SOL
* DIS # H2: 5 => CTR => H2: 6,9
* DIS # C1: 6 => CTR => C1: 5,9
* DIS # F3: 5,9 => CTR => F3: 6
* DIS # F3: 5,9 => CTR => F3: 6
* DIS # H2: 6 => CTR => H2: 5,9
* DIS # F5: 6,9 => CTR => F5: 5
* PRF # F5: 5 => SOL
* PRF # G5: 6,9 => SOL
* DIS # G5: 5 => CTR => G5: 6,9
* DIS # G6: 6,9 => CTR => G6: 5
* PRF # G6: 5 => SOL
* PRF # A9: 6,9 => SOL
* DIS # F5: 6,9 => CTR => F5: 5
* PRF # F5: 5 => SOL
* DIS # E3: 5 => CTR => E3: 6,9
* DIS # F5: 6 => CTR => F5: 5,9
* DIS # G6: 6 => CTR => G6: 5,9
* PRF # G5: 6,9 => SOL
* DIS # G5: 5 => CTR => G5: 6,9
* DIS # G6: 6,9 => CTR => G6: 5
* PRF # G6: 5 => SOL
* PRF # A9: 6,9 => SOL
* PRF # H9: 5 => SOL
* PRF # C1: 6,9 => SOL
* DIS # C1: 5 => CTR => C1: 6,9
* DIS # E3: 6 => CTR => E3: 5,9
* DIS # I8: 5,9 => CTR => I8: 6
* DIS # F3: 5,9 => CTR => F3: 6
* DIS # I8: 5,9 => CTR => I8: 6
* DIS # I1: 6 => CTR => I1: 5,9
* CNT  33 HDP CHAINS /  55 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A6,B2,B5,C3,C9,D2,D6,E4,E7,F8,G4,I7)
* 41.2738..2.7.184.338.4..1278547.2.311.283..74.73.41.827386.421..2138.74..4.1273.8
* PAIR B2: 6,9 BLK 1
C1: 6,9,5                                # reduction candidate for 6,9
C1: 6,9 => SOLVED
* 419273865267518493385496127854762931192835674673941582738654219521389746946127358
* DURATION: 0:00:01.994907  START: 11:10:05.173660  END: 11:10:07.168567 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-244-base-pr-001.dot
* REASONING
* PRF # C1: 6,9 => SOL
* STA C1: 6,9
* CNT   1 HDP CHAINS /   1 HYP OPENED

Header Info

Top 500 Minimum 17 244

solution: 419273865267518493385496127854762931192835674673941582738654219521389746946127358
info: 2069     FNBWX    S8.f     46217

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

Solution

position: 419273865267518493385496127854762931192835674673941582738654219521389746946127358 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 # C1: 6,9 => SOL
* DIS # C1: 5 => CTR => C1: 6,9
* PRF # H2: 6,9 => SOL
* DIS # H2: 5 => CTR => H2: 6,9
* INC # C1: 5,9 => UNS
* DIS # C1: 6 => CTR => C1: 5,9
* INC # E3: 5,9 => UNS
* DIS # F3: 5,9 => CTR => F3: 6
* INC # F3: 6 => UNS
* INC # E3: 5,9 => UNS
* DIS # F3: 5,9 => CTR => F3: 6
* INC # F3: 6 => UNS
* INC # H2: 5,9 => UNS
* DIS # H2: 6 => CTR => H2: 5,9
* DIS # F5: 6,9 => CTR => F5: 5
* PRF # F5: 5 => SOL
* PRF # G5: 6,9 => SOL
* DIS # G5: 5 => CTR => G5: 6,9
* DIS # G6: 6,9 => CTR => G6: 5
* PRF # G6: 5 => SOL
* INC # A8: 6,9 => UNS
* PRF # A9: 6,9 => SOL
* INC # A9: 5 => UNS
* DIS # F5: 6,9 => CTR => F5: 5
* PRF # F5: 5 => SOL
* INC # E3: 6,9 => UNS
* DIS # E3: 5 => CTR => E3: 6,9
* INC # F5: 5,9 => UNS
* DIS # F5: 6 => CTR => F5: 5,9
* INC # G6: 5,9 => UNS
* DIS # G6: 6 => CTR => G6: 5,9
* PRF # G5: 6,9 => SOL
* DIS # G5: 5 => CTR => G5: 6,9
* DIS # G6: 6,9 => CTR => G6: 5
* PRF # G6: 5 => SOL
* INC # A8: 6,9 => UNS
* PRF # A9: 6,9 => SOL
* INC # A9: 5 => UNS
* INC # H9: 6,9 => UNS
* PRF # H9: 5 => SOL
* PRF # C1: 6,9 => SOL
* DIS # C1: 5 => CTR => C1: 6,9
* INC # E3: 5,9 => UNS
* DIS # E3: 6 => CTR => E3: 5,9
* INC # A8: 5,9 => UNS
* DIS # I8: 5,9 => CTR => I8: 6
* INC # I8: 6 => UNS
* DIS # F3: 5,9 => CTR => F3: 6
* INC # F3: 6 => UNS
* INC # F5: 5,9 => UNS
* DIS # I8: 5,9 => CTR => I8: 6
* INC # I8: 6 => UNS
* INC # H9: 5,9 => UNS
* INC # I1: 5,9 => UNS
* DIS # I1: 6 => CTR => I1: 5,9
* CNT  55 HDP CHAINS /  55 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* PRF # C1: 6,9 => SOL
* STA C1: 6,9
* CNT   1 HDP CHAINS /   1 HYP OPENED