Analysis of xx-top500-272-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: .1......2....4..8....6...4.5.7.3....4...8..........1..3.....8.....1..6.....2..... initial

Autosolve

position: .148..3626..342.812..61..4.567431298421.8..36....261.43.2.6481..4.1..62.1.62..4.. autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* DIS # B2: 5 => CTR => B2: 7,9
* DIS # F1: 7,9 => CTR => F1: 5
* DIS # A8: 8 => CTR => A8: 7,9
* DIS # B2: 5,9 => CTR => B2: 7
* DIS # F1: 7,9 => CTR => F1: 5
* DIS # G3: 5 => CTR => G3: 7,9
* DIS # F5: 5 => CTR => F5: 7,9
* DIS # G3: 5 => CTR => G3: 7,9
* DIS # B2: 5 => CTR => B2: 7,9
* DIS # G3: 9 => CTR => G3: 5,7
* DIS # A8: 8,9 => CTR => A8: 7
* DIS # D5: 5,7 => CTR => D5: 9
* DIS # D7: 9 => CTR => D7: 5,7
* DIS # D5: 5,7 => CTR => D5: 9
* DIS # G3: 9 => CTR => G3: 5,7
* CNT  15 HDP CHAINS /  50 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 # B2: 5 => CTR => B2: 7,9
* DIS B2: 7,9 # F1: 7,9 => CTR => F1: 5
* DIS B2: 7,9 + F1: 5 # A8: 8 => CTR => A8: 7,9
* DIS B2: 7,9 + F1: 5 + A8: 7,9 # G3: 5 => CTR => G3: 7,9
* PRF B2: 7,9 + F1: 5 + A8: 7,9 + G3: 7,9 # B9: 8 => SOL
* STA B2: 7,9 + F1: 5 + A8: 7,9 + G3: 7,9 + B9: 8
* CNT   5 HDP CHAINS /  10 HYP OPENED

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

Details

Positions

.1......2....4..8....6...4.5.7.3....4...8..........1..3.....8.....1..6.....2..... initial
.148..3626..342.812..61..4.567431298421.8..36....261.43.2.6481..4.1..62.1.62..4.. autosolve
914875362675342981238619745567431298421987536893526174352764819749158623186293457 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (14)
A1: 7,9
C2: 5,9
B3: 3,8
C3: 3,8
F3: 7,9
G2: 7,9
I3: 5,7
A6: 8,9
D6: 5,7
G5: 5,7
H6: 5,7
F8: 3,8
F9: 3,8
H9: 5,7

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
B3,C3: 3.. / B3 = 3  => 14 pairs (_) / C3 = 3  => 11 pairs (_)
B6,C6: 3.. / B6 = 3  => 11 pairs (_) / C6 = 3  => 14 pairs (_)
F8,F9: 3.. / F8 = 3  => 13 pairs (_) / F9 = 3  => 14 pairs (_)
I8,I9: 3.. / I8 = 3  => 14 pairs (_) / I9 = 3  => 13 pairs (_)
F8,I8: 3.. / F8 = 3  => 13 pairs (_) / I8 = 3  => 14 pairs (_)
F9,I9: 3.. / F9 = 3  => 14 pairs (_) / I9 = 3  => 13 pairs (_)
B3,B6: 3.. / B3 = 3  => 14 pairs (_) / B6 = 3  => 11 pairs (_)
C3,C6: 3.. / C3 = 3  => 11 pairs (_) / C6 = 3  => 14 pairs (_)
B2,C2: 5.. / B2 = 5  =>  0 pairs (X) / C2 = 5  => 15 pairs (_)
E1,F1: 5.. / E1 = 5  =>  0 pairs (X) / F1 = 5  => 17 pairs (_)
G3,I3: 5.. / G3 = 5  =>  0 pairs (X) / I3 = 5  => 17 pairs (_)
G5,H6: 5.. / G5 = 5  => 17 pairs (_) / H6 = 5  =>  0 pairs (X)
D6,H6: 5.. / D6 = 5  => 17 pairs (_) / H6 = 5  =>  0 pairs (X)
C2,C8: 5.. / C2 = 5  => 15 pairs (_) / C8 = 5  =>  0 pairs (X)
F1,F5: 5.. / F1 = 5  => 17 pairs (_) / F5 = 5  =>  0 pairs (X)
G3,G5: 5.. / G3 = 5  =>  0 pairs (X) / G5 = 5  => 17 pairs (_)
H6,H9: 5.. / H6 = 5  =>  0 pairs (X) / H9 = 5  => 17 pairs (_)
A1,B2: 7.. / A1 = 7  =>  0 pairs (X) / B2 = 7  => 19 pairs (_)
G5,H6: 7.. / G5 = 7  =>  0 pairs (X) / H6 = 7  => 17 pairs (_)
B2,G2: 7.. / B2 = 7  => 19 pairs (_) / G2 = 7  =>  0 pairs (X)
D6,H6: 7.. / D6 = 7  =>  0 pairs (X) / H6 = 7  => 17 pairs (_)
A1,A8: 7.. / A1 = 7  =>  0 pairs (X) / A8 = 7  => 19 pairs (_)
H6,H9: 7.. / H6 = 7  => 17 pairs (_) / H9 = 7  =>  0 pairs (X)
B3,C3: 8.. / B3 = 8  => 11 pairs (_) / C3 = 8  => 14 pairs (_)
F8,F9: 8.. / F8 = 8  => 14 pairs (_) / F9 = 8  => 13 pairs (_)
B9,F9: 8.. / B9 = 8  => 14 pairs (_) / F9 = 8  => 13 pairs (_)
A6,A8: 8.. / A6 = 8  => 16 pairs (_) / A8 = 8  =>  0 pairs (X)
G2,G3: 9.. / G2 = 9  => 19 pairs (_) / G3 = 9  =>  0 pairs (X)
D5,F5: 9.. / D5 = 9  => 17 pairs (_) / F5 = 9  =>  0 pairs (X)
F3,G3: 9.. / F3 = 9  => 19 pairs (_) / G3 = 9  =>  0 pairs (X)
D5,D7: 9.. / D5 = 9  => 17 pairs (_) / D7 = 9  =>  0 pairs (X)
* DURATION: 0:01:01.921017  START: 12:12:46.299280  END: 12:13:48.220297 2017-05-04
* CP COUNT: (31)
* CLUE FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A1,A6,B3,C2,C3,D6,F3,F8,F9,G2,G5,H6,H9,I3)
* .148..3626..342.812..61..4.567431298421.8..36....261.43.2.6481..4.1..62.1.62..4..
* PAIR A1: 7,9 BLK 1
B2: 7,9,5                                # reduction candidate for 7,9
B2: 5 => CTR
* 7148..3626593427812..617945567431298421789536...5261.43.2.6481..4.1..62.1.62..4..
B2: 7,9                                  # 15 pairs
* PAIR A1: 7,9 ROW 1
E1: 7,9,5                                # reduction candidate for 7,9
E1: 7,9                                  # 17 pairs
F1: 7,9,5                                # reduction candidate for 7,9
F1: 7,9 => CTR
* .1485.3626753429812..619547567431298421985736...72615439256481..4.1..62.1.62..47.
F1: 5                                    # 17 pairs
* PAIR A1: 7,9 COL A
A8: 7,9,8                                # reduction candidate for 7,9
A8: 8 => CTR
* 7148..3626..3427812..6179455674312984217895369..52617435296481784.1..62.1.62..4..
A8: 7,9                                  # 16 pairs
* PAIR C2: 5,9 BLK 1
B2: 5,9,7                                # reduction candidate for 5,9
B2: 5,9 => CTR
* 7148..3626..3427812..617945567431298421789536...526174352964817.4.1..62.1.62..4..
B2: 7                                    # 19 pairs
* PAIR C2: 5,9 COL C
C8: 5,9,8                                # reduction candidate for 5,9
C8: 5,9                                  # 16 pairs
C8: 8                                    # 10 pairs
* PAIR B3: 3,8 COL B
B6: 3,8,9                                # reduction candidate for 3,8
B6: 9                                    # 14 pairs
B6: 3,8                                  # 13 pairs
* PAIR C3: 3,8 COL C
C6: 3,8,9                                # reduction candidate for 3,8
C6: 3,8                                  # 16 pairs
C6: 9                                    # 10 pairs
* PAIR F3: 7,9 BLK 2
E1: 7,9,5                                # reduction candidate for 7,9
E1: 7,9                                  # 17 pairs
F1: 7,9,5                                # reduction candidate for 7,9
F1: 7,9 => CTR
* .1485.3626753429812..619547567431298421985736...72615439256481..4.1..62.1.62..47.
F1: 5                                    # 17 pairs
* PAIR F3: 7,9 ROW 3
G3: 7,9,5                                # reduction candidate for 7,9
G3: 5 => CTR
* .148..3626..3429812..619547567431298421985736...726154372564819.4.17.62.1.629.47.
G3: 7,9                                  # 17 pairs
* PAIR F3: 7,9 COL F
F5: 7,9,5                                # reduction candidate for 7,9
F5: 5 => CTR
* .1485.3626753429812..619547567431298421985736...72615439256481..4.1..62.1.62..47.
F5: 7,9                                  # 17 pairs
* PAIR G2: 7,9 BLK 3
G3: 7,9,5                                # reduction candidate for 7,9
G3: 5 => CTR
* .148..3626..3429812..619547567431298421985736...726154372564819.4.17.62.1.629.47.
G3: 7,9                                  # 17 pairs
* PAIR G2: 7,9 ROW 2
B2: 7,9,5                                # reduction candidate for 7,9
B2: 5 => CTR
* 7148..3626593427812..617945567431298421789536...5261.43.2.6481..4.1..62.1.62..4..
B2: 7,9                                  # 15 pairs
* PAIR I3: 5,7 BLK 3
G3: 5,7,9                                # reduction candidate for 5,7
G3: 9 => CTR
* .148.53626.53427812..617945567431298421789536...52617435296481774.15.62.1.627.45.
G3: 5,7                                  # 19 pairs
* PAIR I3: 5,7 COL I
I7: 5,7,9                                # reduction candidate for 5,7
I7: 5,7                                  # 17 pairs
I8: 5,7,3,9                              # reduction candidate for 5,7
I8: 5,7                                  # 18 pairs
I9: 5,7,3,9                              # reduction candidate for 5,7
I9: 5,7                                  # 18 pairs
* PAIR A6: 8,9 BLK 4
B6: 8,9,3                                # reduction candidate for 8,9
B6: 8,9                                  # 14 pairs
C6: 8,9,3                                # reduction candidate for 8,9
C6: 8,9                                  # 11 pairs
* PAIR A6: 8,9 COL A
A8: 8,9,7                                # reduction candidate for 8,9
A8: 8,9 => CTR
* 7148..3626..3427812..617945567431298421789536...526174352964817.4.1..62.1.62..4..
A8: 7                                    # 19 pairs
* PAIR D6: 5,7 BLK 5
D5: 5,7,9                                # reduction candidate for 5,7
D5: 5,7 => CTR
* 7148953626953427812..617945567431298421789536...526174352964817.4.15.62.186273459
D5: 9                                    # 17 pairs
F5: 5,7,9                                # reduction candidate for 5,7
F5: 5,7                                  # 17 pairs
* PAIR D6: 5,7 COL D
D7: 5,7,9                                # reduction candidate for 5,7
D7: 9 => CTR
* 7148953626953427812..617945567431298421789536...526174352964817.4.15.62.186273459
D7: 5,7                                  # 17 pairs
* PAIR G5: 5,7 ROW 5
D5: 5,7,9                                # reduction candidate for 5,7
D5: 5,7 => CTR
* 7148953626953427812..617945567431298421789536...526174352964817.4.15.62.186273459
D5: 9                                    # 17 pairs
F5: 5,7,9                                # reduction candidate for 5,7
F5: 5,7                                  # 17 pairs
* PAIR G5: 5,7 COL G
G3: 5,7,9                                # reduction candidate for 5,7
G3: 9 => CTR
* .148.53626.53427812..617945567431298421789536...52617435296481774.15.62.1.627.45.
G3: 5,7                                  # 19 pairs
* PAIR H9: 5,7 BLK 9
I7: 5,7,9                                # reduction candidate for 5,7
I7: 5,7                                  # 17 pairs
I8: 5,7,3,9                              # reduction candidate for 5,7
I8: 5,7                                  # 18 pairs
I9: 5,7,3,9                              # reduction candidate for 5,7
I9: 5,7                                  # 18 pairs
* PAIR H9: 5,7 ROW 9
B9: 5,7,8,9                              # reduction candidate for 5,7
B9: 5,7                                  # 18 pairs
E9: 5,7,9                                # reduction candidate for 5,7
E9: 5,7                                  # 19 pairs
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-272-base-pr-000.dot
* REASONING
* DIS # B2: 5 => CTR => B2: 7,9
* DIS # F1: 7,9 => CTR => F1: 5
* DIS # A8: 8 => CTR => A8: 7,9
* DIS # B2: 5,9 => CTR => B2: 7
* DIS # F1: 7,9 => CTR => F1: 5
* DIS # G3: 5 => CTR => G3: 7,9
* DIS # F5: 5 => CTR => F5: 7,9
* DIS # G3: 5 => CTR => G3: 7,9
* DIS # B2: 5 => CTR => B2: 7,9
* DIS # G3: 9 => CTR => G3: 5,7
* DIS # A8: 8,9 => CTR => A8: 7
* DIS # D5: 5,7 => CTR => D5: 9
* DIS # D7: 9 => CTR => D7: 5,7
* DIS # D5: 5,7 => CTR => D5: 9
* DIS # G3: 9 => CTR => G3: 5,7
* CNT  15 HDP CHAINS /  50 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A1,A6,B3,C2,C3,D6,F3,F8,F9,G2,G5,H6,H9,I3)
* .148..3626..342.812..61..4.567431298421.8..36....261.43.2.6481..4.1..62.1.62..4..
* PAIR A1: 7,9 BLK 1
B2: 7,9,5                                # reduction candidate for 7,9
B2: 5 => CTR
* 7148..3626593427812..617945567431298421789536...5261.43.2.6481..4.1..62.1.62..4..
* PAIR A1: 7,9 ROW 1
E1: 7,9,5                                # reduction candidate for 7,9
E1: 7,9                                  # 18 pairs
F1: 7,9,5                                # reduction candidate for 7,9
F1: 7,9 => CTR
* .1485.3626753429812..619547567431298421985736...72615439256481..4.1..6251562.8473
* RESTART
* PAIR A1: 7,9 COL A
A8: 7,9,8                                # reduction candidate for 7,9
A8: 8 => CTR
* 7148953626953427812..6179455674312984217895369..52617435296481784.1..62.1.62..4..
* PAIR RESTART
* PAIR F3: 7,9 ROW 3
G3: 7,9,5                                # reduction candidate for 7,9
G3: 5 => CTR
* .148.53626.53429812..619547567431298421.8..368...261.43.2.6481..4.1..62.1.62..4..
* PAIR RESTART

* LEVEL 0 PASS 1 ROUND 2 (AUTO SOLVE) (A1,A8,B2,B3,B6,C3,C6,C8,D5,D7,E1,E9,F3,F5,F8,F9,G2,G3,I7)
* .148.53626.5342.812..61..45567431298421.8.5368..526174352.6481..4.15.62.1.62..45.
* PAIR B2: 7,9 COL B
B9: 7,9,8                                # reduction candidate for 7,9
B9: 8 => SOLVED
* 914875362675342981238619745567431298421987536893526174352764819749158623186293457
* DURATION: 0:00:13.359245  START: 12:14:41.629962  END: 12:14:54.989207 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-272-base-pr-001.dot
* REASONING
* DIS # B2: 5 => CTR => B2: 7,9
* DIS B2: 7,9 # F1: 7,9 => CTR => F1: 5
* DIS B2: 7,9 + F1: 5 # A8: 8 => CTR => A8: 7,9
* DIS B2: 7,9 + F1: 5 + A8: 7,9 # G3: 5 => CTR => G3: 7,9
* PRF B2: 7,9 + F1: 5 + A8: 7,9 + G3: 7,9 # B9: 8 => SOL
* STA B2: 7,9 + F1: 5 + A8: 7,9 + G3: 7,9 + B9: 8
* CNT   5 HDP CHAINS /  10 HYP OPENED

Header Info

Top 500 Minimum 17 272

solution: 914875362675342981238619745567431298421987536893526174352764819749158623186293457
info: 2200     FNBHWXY  S8.f     44996

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

Solution

position: 914875362675342981238619745567431298421987536893526174352764819749158623186293457 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 # B2: 7,9 => UNS
* DIS # B2: 5 => CTR => B2: 7,9
* INC # E1: 7,9 => UNS
* DIS # F1: 7,9 => CTR => F1: 5
* INC # F1: 5 => UNS
* INC # A8: 7,9 => UNS
* DIS # A8: 8 => CTR => A8: 7,9
* DIS # B2: 5,9 => CTR => B2: 7
* INC # B2: 7 => UNS
* INC # C8: 5,9 => UNS
* INC # C8: 8 => UNS
* INC # B6: 3,8 => UNS
* INC # B6: 9 => UNS
* INC # C6: 3,8 => UNS
* INC # C6: 9 => UNS
* INC # E1: 7,9 => UNS
* DIS # F1: 7,9 => CTR => F1: 5
* INC # F1: 5 => UNS
* INC # G3: 7,9 => UNS
* DIS # G3: 5 => CTR => G3: 7,9
* INC # F5: 7,9 => UNS
* DIS # F5: 5 => CTR => F5: 7,9
* INC # G3: 7,9 => UNS
* DIS # G3: 5 => CTR => G3: 7,9
* INC # B2: 7,9 => UNS
* DIS # B2: 5 => CTR => B2: 7,9
* INC # G3: 5,7 => UNS
* DIS # G3: 9 => CTR => G3: 5,7
* INC # I7: 5,7 => UNS
* INC # I8: 5,7 => UNS
* INC # I9: 5,7 => UNS
* INC # B6: 8,9 => UNS
* INC # C6: 8,9 => UNS
* DIS # A8: 8,9 => CTR => A8: 7
* INC # A8: 7 => UNS
* DIS # D5: 5,7 => CTR => D5: 9
* INC # D5: 9 => UNS
* INC # F5: 5,7 => UNS
* INC # D7: 5,7 => UNS
* DIS # D7: 9 => CTR => D7: 5,7
* DIS # D5: 5,7 => CTR => D5: 9
* INC # D5: 9 => UNS
* INC # F5: 5,7 => UNS
* INC # G3: 5,7 => UNS
* DIS # G3: 9 => CTR => G3: 5,7
* INC # I7: 5,7 => UNS
* INC # I8: 5,7 => UNS
* INC # I9: 5,7 => UNS
* INC # B9: 5,7 => UNS
* INC # E9: 5,7 => UNS
* CNT  50 HDP CHAINS /  50 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* INC # B2: 7,9 => UNS
* DIS # B2: 5 => CTR => B2: 7,9
* INC B2: 7,9 # E1: 7,9 => UNS
* DIS B2: 7,9 # F1: 7,9 => CTR => F1: 5
* INC B2: 7,9 + F1: 5 # A8: 7,9 => UNS
* DIS B2: 7,9 + F1: 5 # A8: 8 => CTR => A8: 7,9
* INC B2: 7,9 + F1: 5 + A8: 7,9 # G3: 7,9 => UNS
* DIS B2: 7,9 + F1: 5 + A8: 7,9 # G3: 5 => CTR => G3: 7,9
* INC B2: 7,9 + F1: 5 + A8: 7,9 + G3: 7,9 # B9: 7,9 => UNS
* PRF B2: 7,9 + F1: 5 + A8: 7,9 + G3: 7,9 # B9: 8 => SOL
* STA B2: 7,9 + F1: 5 + A8: 7,9 + G3: 7,9 + B9: 8
* CNT  10 HDP CHAINS /  10 HYP OPENED