Analysis of xx-top500-130-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: .6.3.2.....8...41........9..3.5..6......1..2.............7..3..9...2....1........ initial

Autosolve

position: 461392...2986..4133..1..296.325.96.1....13.2..1.2...3..2.7.13.99.3.2.1..1..93...2 autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* DIS # B9: 5,7 => CTR => B9: 4,8
* DIS # E6: 4,8 => CTR => E6: 6,7
* DIS # E7: 4,8 => CTR => E7: 5,6
* DIS # F6: 4,8 => CTR => F6: 6,7
* PRF # F8: 4,8 => SOL
* PRF # A5: 7,8 => SOL
* DIS # E4: 7,8 => CTR => E4: 4
* PRF # E4: 4 => SOL
* PRF # H4: 7,8 => SOL
* DIS # H4: 4 => CTR => H4: 7,8
* DIS # E6: 4,8 => CTR => E6: 6,7
* DIS # F6: 4,8 => CTR => F6: 6,7
* DIS # I5: 4,8 => CTR => I5: 5,7
* DIS # E7: 4,8 => CTR => E7: 5,6
* PRF # F8: 4,8 => SOL
* DIS # B8: 4,8 => CTR => B8: 5,7
* DIS # H8: 4,8 => CTR => H8: 5,6,7
* CNT  17 HDP CHAINS /  40 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 # B9: 5,7 => CTR => B9: 4,8
* DIS B9: 4,8 # B8: 4,8 => CTR => B8: 5,7
* DIS B9: 4,8 + B8: 5,7 # E6: 4,8 => CTR => E6: 6,7
* DIS B9: 4,8 + B8: 5,7 + E6: 6,7 # E7: 4,8 => CTR => E7: 5,6
* PRF B9: 4,8 + B8: 5,7 + E6: 6,7 + E7: 5,6 # F8: 4,8 => SOL
* STA B9: 4,8 + B8: 5,7 + E6: 6,7 + E7: 5,6 + F8: 4,8
* CNT   5 HDP CHAINS /  10 HYP OPENED

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

Details

Positions

.6.3.2.....8...41........9..3.5..6......1..2.............7..3..9...2....1........ initial
461392...2986..4133..1..296.325.96.1....13.2..1.2...3..2.7.13.99.3.2.1..1..93...2 autosolve
461392758298675413375184296832549671746813925519267834624751389953428167187936542 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (9)
B3: 5,7
C3: 5,7
E2: 5,7
F2: 5,7
E3: 4,8
F3: 4,8
A4: 7,8
D5: 4,8
D8: 4,8

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
E3,F3: 4.. / E3 = 4  =>  0 pairs (X) / F3 = 4  =>  8 pairs (_)
E4,H4: 4.. / E4 = 4  =>  0 pairs (*) / H4 = 4  =>  0 pairs (X)
D5,D8: 4.. / D5 = 4  =>  0 pairs (X) / D8 = 4  =>  0 pairs (_)
B3,C3: 5.. / B3 = 5  =>  9 pairs (_) / C3 = 5  => 10 pairs (_)
E2,F2: 5.. / E2 = 5  =>  7 pairs (_) / F2 = 5  => 17 pairs (_)
E2,E7: 5.. / E2 = 5  =>  7 pairs (_) / E7 = 5  => 17 pairs (_)
A5,C5: 6.. / A5 = 6  => 11 pairs (_) / C5 = 6  =>  0 pairs (*)
E6,F6: 6.. / E6 = 6  =>  9 pairs (_) / F6 = 6  => 14 pairs (_)
F8,H8: 6.. / F8 = 6  =>  9 pairs (_) / H8 = 6  =>  9 pairs (_)
A5,A7: 6.. / A5 = 6  => 11 pairs (_) / A7 = 6  =>  0 pairs (*)
E6,E7: 6.. / E6 = 6  =>  9 pairs (_) / E7 = 6  => 14 pairs (_)
B3,C3: 7.. / B3 = 7  => 10 pairs (_) / C3 = 7  =>  9 pairs (_)
E2,F2: 7.. / E2 = 7  => 17 pairs (_) / F2 = 7  =>  7 pairs (_)
C3,C9: 7.. / C3 = 7  =>  9 pairs (_) / C9 = 7  => 10 pairs (_)
F2,F6: 7.. / F2 = 7  =>  7 pairs (_) / F6 = 7  => 17 pairs (_)
E3,F3: 8.. / E3 = 8  =>  8 pairs (_) / F3 = 8  =>  0 pairs (X)
D5,D8: 8.. / D5 = 8  =>  0 pairs (*) / D8 = 8  =>  0 pairs (X)
C5,C6: 9.. / C5 = 9  => 12 pairs (_) / C6 = 9  =>  0 pairs (*)
G5,G6: 9.. / G5 = 9  =>  0 pairs (*) / G6 = 9  =>  0 pairs (X)
C5,G5: 9.. / C5 = 9  => 12 pairs (_) / G5 = 9  =>  0 pairs (*)
C6,G6: 9.. / C6 = 9  =>  0 pairs (*) / G6 = 9  =>  0 pairs (X)
* DURATION: 0:00:36.260069  START: 07:12:43.484598  END: 07:13:19.744667 2017-05-04
* CP COUNT: (21)
* SOLUTION FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A4,B3,C3,D5,D8,E2,E3,F2,F3)
* 461392...2986..4133..1..296.325.96.1....13.2..1.2...3..2.7.13.99.3.2.1..1..93...2
* PAIR B3: 5,7 COL B
B8: 5,7,4,8                              # reduction candidate for 5,7
B8: 5,7                                  # 13 pairs
B9: 5,7,4,8                              # reduction candidate for 5,7
B9: 5,7 => CTR
* 4613927582986..413357184296832549671746813.2..1.2...34.2.7.138998342.1..1..938542
B9: 4,8                                  # 10 pairs
* PAIR C3: 5,7 COL C
C9: 5,7,4,6                              # reduction candidate for 5,7
C9: 5,7                                  # 12 pairs
C9: 4,6                                  #  8 pairs
* PAIR E3: 4,8 COL E
E4: 4,8,7                                # reduction candidate for 4,8
E4: 4,8                                  # 14 pairs
E6: 4,8,6,7                              # reduction candidate for 4,8
E6: 4,8 => CTR
* 461392...29865741335714829683257964164.813.2.71.2.6.3.5247613899.3.2.1641.6934..2
E6: 6,7                                  # 10 pairs
E7: 4,8,5,6                              # reduction candidate for 4,8
E7: 4,8 => CTR
* 461392...2986574133..1..296832579641...413.2..1426893..2.7413899.382.1.41..93...2
E7: 5,6                                  # 10 pairs
* PAIR F3: 4,8 COL F
F6: 4,8,6,7                              # reduction candidate for 4,8
F6: 4,8 => CTR
* 461392...2986574133..1..296832579641...413.2..1426893..2.7413899.382.1.41..93...2
F6: 6,7                                  # 10 pairs
F8: 4,8,5,6                              # reduction candidate for 4,8
F8: 4,8 => SOLVED
* 461392758298675413375184296832549671746813925519267834624751389953428167187936542
F8: 5,6                                  # 10 pairs
F9: 4,8,5,6                              # reduction candidate for 4,8
F9: 4,8                                  # 13 pairs
* PAIR A4: 7,8 BLK 4
A5: 7,8,5,6                              # reduction candidate for 7,8
A5: 7,8 => SOLVED
* 461392758298675413375184296832549671746813925519267834624751389953428167187936542
A5: 5,6                                  # 11 pairs
A6: 7,8,5                                # reduction candidate for 7,8
A6: 7,8                                  # 14 pairs
* PAIR A4: 7,8 ROW 4
E4: 7,8,4                                # reduction candidate for 7,8
E4: 7,8 => CTR
* 461392...2986574133..184296832579641.59413.2.71426893552674138997382.1.414.93...2
E4: 4 => SOLVED
* 461392758298675413375184296832549671746813925519267834624751389953428167187936542
H4: 7,8,4                                # reduction candidate for 7,8
H4: 7,8 => SOLVED
* 461392758298675413375184296832549671746813925519267834624751389953428167187936542
H4: 4 => CTR
* 461392...2986574133..184296832579641.59413.2.71426893552674138997382.1.414.93...2
* PAIR D5: 4,8 BLK 5
E4: 4,8,7                                # reduction candidate for 4,8
E4: 4,8                                  # 14 pairs
E6: 4,8,6,7                              # reduction candidate for 4,8
E6: 4,8 => CTR
* 461392...29865741335714829683257964164.813.2.71.2.6.3.5247613899.3.2.1641.6934..2
E6: 6,7                                  # 10 pairs
F6: 4,8,6,7                              # reduction candidate for 4,8
F6: 4,8 => CTR
* 461392...2986574133..1..296832579641...413.2..1426893..2.7413899.382.1.41..93...2
F6: 6,7                                  # 10 pairs
* PAIR D5: 4,8 ROW 5
B5: 4,8,5                                # reduction candidate for 4,8
B5: 4,8                                  # 11 pairs
I5: 4,8,5,7                              # reduction candidate for 4,8
I5: 4,8 => CTR
* 46139285729865741337518429683257964165941372871426893552674138994382.1..18793.5.2
I5: 5,7                                  # 10 pairs
* PAIR D8: 4,8 BLK 8
E7: 4,8,5,6                              # reduction candidate for 4,8
E7: 4,8 => CTR
* 461392...2986574133..1..296832579641...413.2..1426893..2.7413899.382.1.41..93...2
E7: 5,6                                  # 10 pairs
F8: 4,8,5,6                              # reduction candidate for 4,8
F8: 4,8 => SOLVED
* 461392758298675413375184296832549671746813925519267834624751389953428167187936542
F8: 5,6                                  # 10 pairs
F9: 4,8,5,6                              # reduction candidate for 4,8
F9: 4,8                                  # 13 pairs
* PAIR D8: 4,8 ROW 8
B8: 4,8,5,7                              # reduction candidate for 4,8
B8: 4,8 => CTR
* 461392.5.2986..4133..1842968325496717468139255192...3..2.7.138998342.1..1..938542
B8: 5,7                                  # 13 pairs
H8: 4,8,5,6,7                            # reduction candidate for 4,8
H8: 4,8 => CTR
* 461392...2986..4133..1..296.325496.1...813.2..1.267.3..2.7.13.99.342618.18.935..2
H8: 5,6,7                                #  9 pairs
I8: 4,8,5,7                              # reduction candidate for 4,8
I8: 4,8                                  # 15 pairs
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-130-base-pr-000.dot
* REASONING
* DIS # B9: 5,7 => CTR => B9: 4,8
* DIS # E6: 4,8 => CTR => E6: 6,7
* DIS # E7: 4,8 => CTR => E7: 5,6
* DIS # F6: 4,8 => CTR => F6: 6,7
* PRF # F8: 4,8 => SOL
* PRF # A5: 7,8 => SOL
* DIS # E4: 7,8 => CTR => E4: 4
* PRF # E4: 4 => SOL
* PRF # H4: 7,8 => SOL
* DIS # H4: 4 => CTR => H4: 7,8
* DIS # E6: 4,8 => CTR => E6: 6,7
* DIS # F6: 4,8 => CTR => F6: 6,7
* DIS # I5: 4,8 => CTR => I5: 5,7
* DIS # E7: 4,8 => CTR => E7: 5,6
* PRF # F8: 4,8 => SOL
* DIS # B8: 4,8 => CTR => B8: 5,7
* DIS # H8: 4,8 => CTR => H8: 5,6,7
* CNT  17 HDP CHAINS /  40 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A4,B3,C3,D5,D8,E2,E3,F2,F3)
* 461392...2986..4133..1..296.325.96.1....13.2..1.2...3..2.7.13.99.3.2.1..1..93...2
* PAIR B3: 5,7 COL B
B8: 5,7,4,8                              # reduction candidate for 5,7
B8: 5,7                                  # 13 pairs
B9: 5,7,4,8                              # reduction candidate for 5,7
B9: 5,7 => CTR
* 4613927582986..413357184296832549671746813.2..1.2...34.2.7.138998342.1..1..938542
* RESTART
* PAIR B3: 5,7 COL B
B8: 5,7,4,8                              # reduction candidate for 5,7
B8: 4,8 => CTR
* 461392...2986574133751..296.3257964165..13.2.71.26..3.5267413899.382.1.41.793...2
* PAIR RESTART
* PAIR C3: 5,7 COL C
C9: 5,7,4,6                              # reduction candidate for 5,7
C9: 5,7                                  # 18 pairs
C9: 4,6                                  #  9 pairs
* PAIR E3: 4,8 COL E
E4: 4,8,7                                # reduction candidate for 4,8
E4: 4,8                                  # 18 pairs
E6: 4,8,6,7                              # reduction candidate for 4,8
E6: 4,8 => CTR
* 461392...2986574133.71..296.325796416...13.2.71.2.6.3.524761389973.2.164186934..2
E7: 4,8,5,6                              # reduction candidate for 4,8
E7: 4,8 => CTR
* 461392...2986574133..1..296832579641.4..13.2..1.26..3..2.7.13.99.3.2.1.41..93...2
* RESTART
* PAIR RESTART
* PAIR F3: 4,8 COL F
F8: 4,8,5,6                              # reduction candidate for 4,8
F8: 4,8 => SOLVED
* 461392758298675413375184296832549671746813925519267834624751389953428167187936542
* DURATION: 0:00:12.203700  START: 07:13:58.271779  END: 07:14:10.475479 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-130-base-pr-001.dot
* REASONING
* DIS # B9: 5,7 => CTR => B9: 4,8
* DIS B9: 4,8 # B8: 4,8 => CTR => B8: 5,7
* DIS B9: 4,8 + B8: 5,7 # E6: 4,8 => CTR => E6: 6,7
* DIS B9: 4,8 + B8: 5,7 + E6: 6,7 # E7: 4,8 => CTR => E7: 5,6
* PRF B9: 4,8 + B8: 5,7 + E6: 6,7 + E7: 5,6 # F8: 4,8 => SOL
* STA B9: 4,8 + B8: 5,7 + E6: 6,7 + E7: 5,6 + F8: 4,8
* CNT   5 HDP CHAINS /  10 HYP OPENED

Header Info

Top 500 Minimum 17 130

solution: 461392758298675413375184296832549671746813925519267834624751389953428167187936542
info: 1811     FNBWXY   S8.f     21420

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

Solution

position: 461392758298675413375184296832549671746813925519267834624751389953428167187936542 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 # B8: 5,7 => UNS
* DIS # B9: 5,7 => CTR => B9: 4,8
* INC # B9: 4,8 => UNS
* INC # C9: 5,7 => UNS
* INC # C9: 4,6 => UNS
* INC # E4: 4,8 => UNS
* DIS # E6: 4,8 => CTR => E6: 6,7
* INC # E6: 6,7 => UNS
* DIS # E7: 4,8 => CTR => E7: 5,6
* INC # E7: 5,6 => UNS
* DIS # F6: 4,8 => CTR => F6: 6,7
* INC # F6: 6,7 => UNS
* PRF # F8: 4,8 => SOL
* INC # F8: 5,6 => UNS
* INC # F9: 4,8 => UNS
* PRF # A5: 7,8 => SOL
* INC # A5: 5,6 => UNS
* INC # A6: 7,8 => UNS
* DIS # E4: 7,8 => CTR => E4: 4
* PRF # E4: 4 => SOL
* PRF # H4: 7,8 => SOL
* DIS # H4: 4 => CTR => H4: 7,8
* INC # E4: 4,8 => UNS
* DIS # E6: 4,8 => CTR => E6: 6,7
* INC # E6: 6,7 => UNS
* DIS # F6: 4,8 => CTR => F6: 6,7
* INC # F6: 6,7 => UNS
* INC # B5: 4,8 => UNS
* DIS # I5: 4,8 => CTR => I5: 5,7
* INC # I5: 5,7 => UNS
* DIS # E7: 4,8 => CTR => E7: 5,6
* INC # E7: 5,6 => UNS
* PRF # F8: 4,8 => SOL
* INC # F8: 5,6 => UNS
* INC # F9: 4,8 => UNS
* DIS # B8: 4,8 => CTR => B8: 5,7
* INC # B8: 5,7 => UNS
* DIS # H8: 4,8 => CTR => H8: 5,6,7
* INC # H8: 5,6,7 => UNS
* INC # I8: 4,8 => UNS
* CNT  40 HDP CHAINS /  40 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* INC # B8: 5,7 => UNS
* DIS # B9: 5,7 => CTR => B9: 4,8
* INC B9: 4,8 # B8: 5,7 => UNS
* DIS B9: 4,8 # B8: 4,8 => CTR => B8: 5,7
* INC B9: 4,8 + B8: 5,7 # C9: 5,7 => UNS
* INC B9: 4,8 + B8: 5,7 # C9: 4,6 => UNS
* INC B9: 4,8 + B8: 5,7 # E4: 4,8 => UNS
* DIS B9: 4,8 + B8: 5,7 # E6: 4,8 => CTR => E6: 6,7
* DIS B9: 4,8 + B8: 5,7 + E6: 6,7 # E7: 4,8 => CTR => E7: 5,6
* PRF B9: 4,8 + B8: 5,7 + E6: 6,7 + E7: 5,6 # F8: 4,8 => SOL
* STA B9: 4,8 + B8: 5,7 + E6: 6,7 + E7: 5,6 + F8: 4,8
* CNT  10 HDP CHAINS /  10 HYP OPENED