Analysis of xx-top500-465-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: 1...6..7.7.2......4..8.....3....4....6.....9....2...........4.2.5..9..........6.. initial

Autosolve

position: 1.5.6..7.7.2......4.68.....3....4....6.....9....2...........4.2.5..9..........6.9 autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* DIS # F3: 3,9 => CTR => F3: 1,2,5,7
* PRF # C7: 1,7 => SOL
* DIS # B9: 1,7 => CTR => B9: 2,4
* PRF # B4: 1,7 => SOL
* DIS # B4: 2 => CTR => B4: 1,7
* DIS # B6: 1,7 => CTR => B6: 4
* PRF # B6: 4 => SOL
* DIS # A8: 2,8 => CTR => A8: 6
* PRF # A8: 6 => SOL
* DIS # E9: 2,8 => CTR => E9: 1,3,4,5,7
* PRF # E9: 1,3,4,5,7 => SOL
* DIS # F9: 2,8 => CTR => F9: 1,3,5,7
* PRF # A5: 2,8 => SOL
* DIS # A5: 5 => CTR => A5: 2,8
* CNT  14 HDP CHAINS /  25 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 # F3: 3,9 => CTR => F3: 1,2,5,7
* PRF F3: 1,2,5,7 # C7: 1,7 => SOL
* STA F3: 1,2,5,7 + C7: 1,7
* CNT   2 HDP CHAINS /  11 HYP OPENED

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

Details

Positions

1...6..7.7.2......4..8.....3....4....6.....9....2...........4.2.5..9..........6.. initial
1.5.6..7.7.2......4.68.....3....4....6.....9....2...........4.2.5..9..........6.9 autosolve
195463278782915346436827915319654827267138594548279163971586432654392781823741659 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (5)
B3: 3,9
D4: 6,9
F6: 6,9
B7: 1,7
A9: 2,8

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
B4,A5: 2.. / B4 = 2  =>  0 pairs (X) / A5 = 2  =>  0 pairs (_)
F1,G1: 2.. / F1 = 2  =>  0 pairs (X) / G1 = 2  =>  0 pairs (_)
A5,G5: 2.. / A5 = 2  =>  0 pairs (*) / G5 = 2  =>  0 pairs (X)
A8,F8: 2.. / A8 = 2  =>  0 pairs (X) / F8 = 2  =>  0 pairs (_)
B4,B9: 2.. / B4 = 2  =>  0 pairs (X) / B9 = 2  =>  0 pairs (_)
E3,E9: 2.. / E3 = 2  =>  0 pairs (*) / E9 = 2  =>  0 pairs (X)
H3,H4: 2.. / H3 = 2  =>  0 pairs (X) / H4 = 2  =>  0 pairs (_)
D1,I1: 4.. / D1 = 4  =>  0 pairs (*) / I1 = 4  =>  0 pairs (X)
C5,I5: 4.. / C5 = 4  =>  0 pairs (X) / I5 = 4  =>  0 pairs (_)
C8,D8: 4.. / C8 = 4  =>  0 pairs (*) / D8 = 4  =>  0 pairs (X)
B6,B9: 4.. / B6 = 4  =>  0 pairs (*) / B9 = 4  =>  0 pairs (X)
E2,E9: 4.. / E2 = 4  =>  0 pairs (X) / E9 = 4  =>  0 pairs (_)
H2,H6: 4.. / H2 = 4  =>  0 pairs (*) / H6 = 4  =>  0 pairs (X)
A5,A6: 5.. / A5 = 5  =>  0 pairs (X) / A6 = 5  =>  0 pairs (_)
H7,H9: 5.. / H7 = 5  =>  5 pairs (_) / H9 = 5  =>  5 pairs (_)
H2,I2: 6.. / H2 = 6  =>  0 pairs (X) / I2 = 6  =>  5 pairs (_)
D4,F6: 6.. / D4 = 6  =>  0 pairs (*) / F6 = 6  =>  0 pairs (X)
A7,A8: 6.. / A7 = 6  =>  0 pairs (X) / A8 = 6  =>  0 pairs (_)
E3,F3: 7.. / E3 = 7  =>  0 pairs (X) / F3 = 7  =>  5 pairs (_)
G8,I8: 7.. / G8 = 7  =>  5 pairs (_) / I8 = 7  =>  5 pairs (_)
B1,B2: 8.. / B1 = 8  =>  7 pairs (_) / B2 = 8  =>  6 pairs (_)
D4,F6: 9.. / D4 = 9  =>  4 pairs (_) / F6 = 9  =>  0 pairs (*)
A7,C7: 9.. / A7 = 9  =>  0 pairs (*) / C7 = 9  =>  0 pairs (X)
C4,D4: 9.. / C4 = 9  =>  0 pairs (*) / D4 = 9  =>  0 pairs (X)
A6,A7: 9.. / A6 = 9  =>  0 pairs (X) / A7 = 9  =>  0 pairs (_)
* DURATION: 0:00:44.210884  START: 18:36:36.809938  END: 18:37:21.020822 2017-05-04
* CP COUNT: (25)
* SOLUTION FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A9,B3,B7,D4,F6)
* 1.5.6..7.7.2......4.68.....3....4....6.....9....2...........4.2.5..9..........6.9
* PAIR B3: 3,9 BLK 1
B1: 3,9,8                                # reduction candidate for 3,9
B1: 3,9                                  #  6 pairs
B2: 3,9,8                                # reduction candidate for 3,9
B2: 3,9                                  #  7 pairs
* PAIR B3: 3,9 ROW 3
F3: 3,9,1,2,5,7                          # reduction candidate for 3,9
F3: 3,9 => CTR
* 1.5.62.747.2.4....4.687..2.32...4...564...29.9..2.6.4.6.9...4.225..9....84..2.6.9
F3: 1,2,5,7                              #  5 pairs
G3: 3,9,1,2,5                            # reduction candidate for 3,9
G3: 3,9                                  #  8 pairs
* PAIR B7: 1,7 BLK 7
C7: 1,7,3,8,9                            # reduction candidate for 1,7
C7: 1,7 => SOLVED
* 195463278782915346436827915319654827267138594548279163971586432654392781823741659
C7: 3,8,9                                #  5 pairs
B9: 1,7,2,4                              # reduction candidate for 1,7
B9: 1,7 => CTR
* 1.5.62.7.7.2....464.68...2.32...4....6....294.4.2...........4.225..9....8.....6.9
B9: 2,4                                  #  6 pairs
C9: 1,7,3,4,8                            # reduction candidate for 1,7
C9: 1,7                                  #  7 pairs
* PAIR B7: 1,7 ROW 7
D7: 1,7,3,5,6                            # reduction candidate for 1,7
D7: 1,7                                  #  6 pairs
E7: 1,7,3,5,8                            # reduction candidate for 1,7
E7: 1,7                                  #  6 pairs
F7: 1,7,3,5,6,8                          # reduction candidate for 1,7
F7: 1,7                                  #  6 pairs
* PAIR B7: 1,7 COL B
B4: 1,7,2                                # reduction candidate for 1,7
B4: 1,7 => SOLVED
* 195463278782915346436827915319654827267138594548279163971586432654392781823741659
B4: 2 => CTR
* 1.5.62.7.7.2.4....4.68...2.32...4...56....29.9..2.6.4.6.9...4.225.69....84..2.6.9
B6: 1,7,4                                # reduction candidate for 1,7
B6: 1,7 => CTR
* 1.5.62.747.2.4....4.68...2.32.6.4...564...29.9..2...4.......4.225.496...84..2.6.9
B6: 4 => SOLVED
* 195463278782915346436827915319654827267138594548279163971586432654392781823741659
* PAIR A9: 2,8 BLK 7
A8: 2,8,6                                # reduction candidate for 2,8
A8: 2,8 => CTR
* 1.5462.7.7.2....464.68...2.32.9.4.6.56....29494.2.6...6.9...4.225469....8.3.2.6.9
A8: 6 => SOLVED
* 195463278782915346436827915319654827267138594548279163971586432654392781823741659
* PAIR A9: 2,8 ROW 9
E9: 2,8,1,3,4,5,7                        # reduction candidate for 2,8
E9: 2,8 => CTR
* 1.5.62.747.2.4....4.68...2.32.6.4...564...29.9..2...4.......4.225.496...84..2.6.9
E9: 1,3,4,5,7 => SOLVED
* 195463278782915346436827915319654827267138594548279163971586432654392781823741659
F9: 2,8,1,3,5,7                          # reduction candidate for 2,8
F9: 2,8 => CTR
* 1.5.6..7.7.2......4.6827...32...4....6....29....2...........4.2.5..9..........6.9
F9: 1,3,5,7                              #  5 pairs
* PAIR A9: 2,8 COL A
A5: 2,8,5                                # reduction candidate for 2,8
A5: 2,8 => SOLVED
* 195463278782915346436827915319654827267138594548279163971586432654392781823741659
A5: 5 => CTR
* 1.5.62.7.7.2.4....4.68...2.32...4...56....29.9..2.6.4.6.9...4.225.69....84..2.6.9
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-465-base-pr-000.dot
* REASONING
* DIS # F3: 3,9 => CTR => F3: 1,2,5,7
* PRF # C7: 1,7 => SOL
* DIS # B9: 1,7 => CTR => B9: 2,4
* PRF # B4: 1,7 => SOL
* DIS # B4: 2 => CTR => B4: 1,7
* DIS # B6: 1,7 => CTR => B6: 4
* PRF # B6: 4 => SOL
* DIS # A8: 2,8 => CTR => A8: 6
* PRF # A8: 6 => SOL
* DIS # E9: 2,8 => CTR => E9: 1,3,4,5,7
* PRF # E9: 1,3,4,5,7 => SOL
* DIS # F9: 2,8 => CTR => F9: 1,3,5,7
* PRF # A5: 2,8 => SOL
* DIS # A5: 5 => CTR => A5: 2,8
* CNT  14 HDP CHAINS /  25 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A9,B3,B7,D4,F6)
* 1.5.6..7.7.2......4.68.....3....4....6.....9....2...........4.2.5..9..........6.9
* PAIR B3: 3,9 BLK 1
B1: 3,9,8                                # reduction candidate for 3,9
B1: 3,9                                  #  6 pairs
B2: 3,9,8                                # reduction candidate for 3,9
B2: 3,9                                  #  7 pairs
* PAIR B3: 3,9 ROW 3
F3: 3,9,1,2,5,7                          # reduction candidate for 3,9
F3: 3,9 => CTR
* 1.5.62.747.2.4....4.687..2.32...4...564...29.9..2.6.4.6.9...4.225..9....84..2.6.9
G3: 3,9,1,2,5                            # reduction candidate for 3,9
G3: 3,9                                  #  8 pairs
* RESTART
* PAIR B3: 3,9 ROW 3
G3: 3,9,1,2,5                            # reduction candidate for 3,9
G3: 3,9                                  #  8 pairs
G3: 1,2,5                                #  6 pairs
* PAIR RESTART
* PAIR B3: 3,9 BLK 1
B1: 3,9,8                                # reduction candidate for 3,9
B1: 3,9                                  #  6 pairs
B2: 3,9,8                                # reduction candidate for 3,9
B2: 3,9                                  #  7 pairs
* PAIR B3: 3,9 ROW 3
G3: 3,9,1,2,5                            # reduction candidate for 3,9
G3: 3,9                                  #  8 pairs
G3: 1,2,5                                #  6 pairs
* PAIR B7: 1,7 BLK 7
C7: 1,7,3,8,9                            # reduction candidate for 1,7
C7: 1,7 => SOLVED
* 195463278782915346436827915319654827267138594548279163971586432654392781823741659
* DURATION: 0:00:09.400793  START: 18:37:44.021185  END: 18:37:53.421978 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-465-base-pr-001.dot
* REASONING
* DIS # F3: 3,9 => CTR => F3: 1,2,5,7
* PRF F3: 1,2,5,7 # C7: 1,7 => SOL
* STA F3: 1,2,5,7 + C7: 1,7
* CNT   2 HDP CHAINS /  11 HYP OPENED

Header Info

Top 500 Minimum 17 465

solution: 195463278782915346436827915319654827267138594548279163971586432654392781823741659
info: 95552    FNBHWYK  S8.f     25360

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

Solution

position: 195463278782915346436827915319654827267138594548279163971586432654392781823741659 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 # B1: 3,9 => UNS
* INC # B2: 3,9 => UNS
* DIS # F3: 3,9 => CTR => F3: 1,2,5,7
* INC # F3: 1,2,5,7 => UNS
* INC # G3: 3,9 => UNS
* PRF # C7: 1,7 => SOL
* INC # C7: 3,8,9 => UNS
* DIS # B9: 1,7 => CTR => B9: 2,4
* INC # B9: 2,4 => UNS
* INC # C9: 1,7 => UNS
* INC # D7: 1,7 => UNS
* INC # E7: 1,7 => UNS
* INC # F7: 1,7 => UNS
* PRF # B4: 1,7 => SOL
* DIS # B4: 2 => CTR => B4: 1,7
* DIS # B6: 1,7 => CTR => B6: 4
* PRF # B6: 4 => SOL
* DIS # A8: 2,8 => CTR => A8: 6
* PRF # A8: 6 => SOL
* DIS # E9: 2,8 => CTR => E9: 1,3,4,5,7
* PRF # E9: 1,3,4,5,7 => SOL
* DIS # F9: 2,8 => CTR => F9: 1,3,5,7
* INC # F9: 1,3,5,7 => UNS
* PRF # A5: 2,8 => SOL
* DIS # A5: 5 => CTR => A5: 2,8
* CNT  25 HDP CHAINS /  25 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* INC # B1: 3,9 => UNS
* INC # B2: 3,9 => UNS
* DIS # F3: 3,9 => CTR => F3: 1,2,5,7
* INC F3: 1,2,5,7 # G3: 3,9 => UNS
* INC F3: 1,2,5,7 # G3: 3,9 => UNS
* INC F3: 1,2,5,7 # G3: 1,2,5 => UNS
* INC F3: 1,2,5,7 # B1: 3,9 => UNS
* INC F3: 1,2,5,7 # B2: 3,9 => UNS
* INC F3: 1,2,5,7 # G3: 3,9 => UNS
* INC F3: 1,2,5,7 # G3: 1,2,5 => UNS
* PRF F3: 1,2,5,7 # C7: 1,7 => SOL
* STA F3: 1,2,5,7 + C7: 1,7
* CNT  11 HDP CHAINS /  11 HYP OPENED