Analysis of xx-top500-266-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: ....38.6..24...................7.2...1.4.....8......3....6..4.1..6...5..3........ initial

Autosolve

position: 1..238.64.241..385.38....12.6.371248.1348.65.84....13..8.6.34.14.681.5.33.1...8.6 autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* DIS # F2: 6,9 => CTR => F2: 7
* DIS # E3: 6,9 => CTR => E3: 4,5
* DIS # F3: 6,9 => CTR => F3: 4,5,7
* DIS # A2: 7 => CTR => A2: 6,9
* DIS # A3: 7,9 => CTR => A3: 6
* DIS # F3: 7,9 => CTR => F3: 4,5,6
* DIS # A7: 5,9 => CTR => A7: 2,7
* DIS # C7: 5,9 => CTR => C7: 2,7
* DIS # A7: 5,9 => CTR => A7: 2,7
* DIS # C7: 5,9 => CTR => C7: 2,7
* DIS # F6: 2,9 => CTR => F6: 5,6
* DIS # F9: 2,9 => CTR => F9: 4,5,7
* DIS # E6: 5,9 => CTR => E6: 2,6
* DIS # F6: 5,9 => CTR => F6: 2,6
* DIS # D9: 5,9 => CTR => D9: 7
* DIS # C7: 7,9 => CTR => C7: 2,5
* PRF # H8: 7,9 => SOL
* DIS # D9: 5,9 => CTR => D9: 7
* PRF # E9: 5,9 => SOL
* DIS # F9: 5,9 => CTR => F9: 2,4,7
* DIS # A7: 5,9 => CTR => A7: 2,7
* DIS # C7: 5,9 => CTR => C7: 2,7
* DIS # E3: 5,9 => CTR => E3: 4,6
* DIS # E6: 5,9 => CTR => E6: 2,6
* PRF # H8: 7,9 => SOL
* DIS # C7: 7,9 => CTR => C7: 2,5
* CNT  26 HDP CHAINS /  68 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 # F2: 6,9 => CTR => F2: 7
* DIS F2: 7 # E3: 6,9 => CTR => E3: 4,5
* DIS F2: 7 + E3: 4,5 # E6: 6,9 => CTR => E6: 2,5
* PRF F2: 7 + E3: 4,5 + E6: 2,5 => SOL
* STA F2: 7 + E3: 4,5 + E6: 2,5
* CNT   4 HDP CHAINS /   3 HYP OPENED

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

Details

Positions

....38.6..24...................7.2...1.4.....8......3....6..4.1..6...5..3........ initial
1..238.64.241..385.38....12.6.371248.1348.65.84....13..8.6.34.14.681.5.33.1...8.6 autosolve
175238964924167385638945712569371248213489657847526139782653491496812573351794826 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (14)
E2: 6,9
G1: 7,9
G3: 7,9
A4: 5,9
C4: 5,9
A5: 2,7
C6: 2,7
F5: 2,9
D6: 5,9
I5: 7,9
I6: 7,9
B8: 7,9
E7: 5,9
H7: 7,9

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
A5,C6: 2.. / A5 = 2  => 19 pairs (_) / C6 = 2  =>  0 pairs (X)
A7,C7: 2.. / A7 = 2  =>  0 pairs (X) / C7 = 2  => 19 pairs (_)
H8,H9: 2.. / H8 = 2  => 18 pairs (_) / H9 = 2  =>  0 pairs (*)
A5,F5: 2.. / A5 = 2  => 19 pairs (_) / F5 = 2  =>  0 pairs (X)
F8,H8: 2.. / F8 = 2  =>  0 pairs (*) / H8 = 2  =>  0 pairs (X)
A5,A7: 2.. / A5 = 2  => 19 pairs (_) / A7 = 2  =>  0 pairs (X)
C6,C7: 2.. / C6 = 2  =>  0 pairs (X) / C7 = 2  => 19 pairs (_)
E6,E9: 2.. / E6 = 2  =>  0 pairs (*) / E9 = 2  =>  0 pairs (X)
E3,F3: 4.. / E3 = 4  => 14 pairs (_) / F3 = 4  =>  0 pairs (X)
E9,F9: 4.. / E9 = 4  =>  0 pairs (X) / F9 = 4  => 14 pairs (_)
E3,E9: 4.. / E3 = 4  => 14 pairs (_) / E9 = 4  =>  0 pairs (X)
F3,F9: 4.. / F3 = 4  =>  0 pairs (X) / F9 = 4  => 14 pairs (_)
B1,C1: 5.. / B1 = 5  => 26 pairs (_) / C1 = 5  => 14 pairs (_)
A4,C4: 5.. / A4 = 5  => 13 pairs (_) / C4 = 5  =>  0 pairs (X)
A4,A7: 5.. / A4 = 5  => 13 pairs (_) / A7 = 5  =>  0 pairs (X)
B1,B9: 5.. / B1 = 5  => 26 pairs (_) / B9 = 5  => 14 pairs (_)
A2,A3: 6.. / A2 = 6  =>  0 pairs (X) / A3 = 6  => 15 pairs (_)
E6,F6: 6.. / E6 = 6  => 18 pairs (_) / F6 = 6  => 17 pairs (_)
G1,G3: 7.. / G1 = 7  =>  0 pairs (X) / G3 = 7  => 21 pairs (_)
A5,C6: 7.. / A5 = 7  =>  0 pairs (X) / C6 = 7  => 19 pairs (_)
I5,I6: 7.. / I5 = 7  => 19 pairs (_) / I6 = 7  =>  0 pairs (X)
A2,F2: 7.. / A2 = 7  =>  0 pairs (X) / F2 = 7  => 21 pairs (_)
A5,I5: 7.. / A5 = 7  =>  0 pairs (X) / I5 = 7  => 19 pairs (_)
C6,I6: 7.. / C6 = 7  => 19 pairs (_) / I6 = 7  =>  0 pairs (X)
D3,D9: 7.. / D3 = 7  =>  0 pairs (X) / D9 = 7  => 21 pairs (_)
G1,G3: 9.. / G1 = 9  => 21 pairs (_) / G3 = 9  =>  0 pairs (X)
A4,C4: 9.. / A4 = 9  =>  0 pairs (X) / C4 = 9  => 13 pairs (_)
I5,I6: 9.. / I5 = 9  =>  0 pairs (X) / I6 = 9  => 19 pairs (_)
F5,I5: 9.. / F5 = 9  => 19 pairs (_) / I5 = 9  =>  0 pairs (X)
* DURATION: 0:00:51.819398  START: 11:57:55.176272  END: 11:58:46.995670 2017-05-04
* CP COUNT: (29)
* SOLUTION FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A4,A5,B8,C4,C6,D6,E2,E7,F5,G1,G3,H7,I5,I6)
* 1..238.64.241..385.38....12.6.371248.1348.65.84....13..8.6.34.14.681.5.33.1...8.6
* PAIR E2: 6,9 BLK 2
F2: 6,9,7                                # reduction candidate for 6,9
F2: 6,9 => CTR
* 1..2387647241963856387..912.6.37124821348965784756213998265347147681.5.33.1...8.6
F2: 7                                    # 21 pairs
E3: 6,9,4,5                              # reduction candidate for 6,9
E3: 6,9 => CTR
* 1..238.64.241..385.385.4.12.6.371248.1348.65.84.92.13..8.6.34.14.681.5.33.1.4.8.6
E3: 4,5                                  # 15 pairs
F3: 6,9,4,5,7                            # reduction candidate for 6,9
F3: 6,9 => CTR
* 19.238.64.241.7385.38546.12.6.37124871348265984296513728.6.34.14.68195233.1724896
F3: 4,5,7                                # 14 pairs
* PAIR E2: 6,9 ROW 2
A2: 6,9,7                                # reduction candidate for 6,9
A2: 7 => CTR
* 1..2387647241963856387..912.6.37124821348965784756213998265347147681.5.33.1...8.6
A2: 6,9                                  # 21 pairs
* PAIR E2: 6,9 COL E
E6: 6,9,2,5                              # reduction candidate for 6,9
E6: 2,5                                  # 18 pairs
E6: 6,9                                  # 17 pairs
* PAIR G1: 7,9 ROW 1
B1: 7,9,5                                # reduction candidate for 7,9
B1: 7,9                                  # 14 pairs
C1: 7,9,5                                # reduction candidate for 7,9
C1: 7,9                                  # 26 pairs
* PAIR G3: 7,9 ROW 3
A3: 7,9,6                                # reduction candidate for 7,9
A3: 7,9 => CTR
* 1.5238.64624197385.385...125693712487134826598429651372876534914.681.5.33517..8.6
A3: 6                                    # 15 pairs
D3: 7,9,5                                # reduction candidate for 7,9
D3: 7,9                                  # 18 pairs
F3: 7,9,4,5,6                            # reduction candidate for 7,9
F3: 7,9 => CTR
* 1..238.64.241.6385638547912.6.37124871348265984296513728.6.34.14.68195233.1724896
F3: 4,5,6                                # 14 pairs
* PAIR A4: 5,9 COL A
A7: 5,9,2,7                              # reduction candidate for 5,9
A7: 5,9 => CTR
* 1..238764.2419.385.387..912.6.371248213489657847526139.826.34714.681.5.33.19..826
A7: 2,7                                  # 21 pairs
* PAIR C4: 5,9 COL C
C1: 5,9,7                                # reduction candidate for 5,9
C1: 5,9                                  # 16 pairs
C7: 5,9,2,7                              # reduction candidate for 5,9
C7: 5,9 => CTR
* 1.7238964.241.7385.38.4.712569371248713482659842...1372856.34714.681.5.33.1.24896
C7: 2,7                                  # 16 pairs
* PAIR A5: 2,7 COL A
A7: 2,7,5,9                              # reduction candidate for 2,7
A7: 5,9 => CTR
* 1..238764.2419.385.387..912.6.371248213489657847526139.826.34714.681.5.33.19..826
A7: 2,7                                  # 21 pairs
* PAIR C6: 2,7 COL C
C7: 2,7,5,9                              # reduction candidate for 2,7
C7: 5,9 => CTR
* 1.7238964.241.7385.38.4.712569371248713482659842...1372856.34714.681.5.33.1.24896
C7: 2,7                                  # 16 pairs
* PAIR F5: 2,9 BLK 5
E6: 2,9,5,6                              # reduction candidate for 2,9
E6: 2,9                                  # 20 pairs
F6: 2,9,5,6                              # reduction candidate for 2,9
F6: 2,9 => CTR
* 1.5238.64.24196385638745912569371248.1348.65.84.56.13.98.6534.14.681.523351924876
F6: 5,6                                  # 15 pairs
* PAIR F5: 2,9 COL F
F8: 2,9,7                                # reduction candidate for 2,9
F8: 2,9                                  # 19 pairs
F9: 2,9,4,5,7                            # reduction candidate for 2,9
F9: 2,9 => CTR
* 1..238.64.241..385.38..4.12.6.371248.1348.65.84...513..8.6.34.14.681.5.33.1.4.8.6
F9: 4,5,7                                # 14 pairs
* PAIR D6: 5,9 BLK 5
E6: 5,9,2,6                              # reduction candidate for 5,9
E6: 5,9 => CTR
* 1..238.6492416738563894571256937124871348265984259613728.65349147681.5233.1.248.6
E6: 2,6                                  # 15 pairs
F6: 5,9,2,6                              # reduction candidate for 5,9
F6: 5,9 => CTR
* 1.5238.64.2419.385.38.4..12569371248713482659842.6.137287653491496817523351924876
F6: 2,6                                  # 17 pairs
* PAIR D6: 5,9 COL D
D3: 5,9,7                                # reduction candidate for 5,9
D3: 5,9                                  # 21 pairs
D9: 5,9,7                                # reduction candidate for 5,9
D9: 5,9 => CTR
* 1..2387647241963856387..912.6.3712482134896578475..139.826.34714.681.5.33.19..826
D9: 7                                    # 21 pairs
* PAIR B8: 7,9 BLK 7
A7: 7,9,2,5                              # reduction candidate for 7,9
A7: 7,9                                  # 16 pairs
C7: 7,9,2,5                              # reduction candidate for 7,9
C7: 7,9 => CTR
* 1.5238.64.241..385.38.4..12569371248713482659842...137287653491496817523351924876
C7: 2,5                                  # 15 pairs
B9: 7,9,5                                # reduction candidate for 7,9
B9: 7,9                                  # 26 pairs
* PAIR B8: 7,9 ROW 8
F8: 7,9,2                                # reduction candidate for 7,9
F8: 7,9                                  # 18 pairs
H8: 7,9,2                                # reduction candidate for 7,9
H8: 7,9 => SOLVED
* 175238964924167385638945712569371248213489657847526139782653491496812573351794826
H8: 2                                    # 18 pairs
* PAIR B8: 7,9 COL B
B1: 7,9,5                                # reduction candidate for 7,9
B1: 5                                    # 26 pairs
B1: 7,9                                  # 14 pairs
* PAIR E7: 5,9 BLK 8
D9: 5,9,7                                # reduction candidate for 5,9
D9: 5,9 => CTR
* 1..2387647241963856387..912.6.3712482134896578475..139.826.34714.681.5.33.19..826
D9: 7                                    # 21 pairs
E9: 5,9,2,4                              # reduction candidate for 5,9
E9: 5,9 => SOLVED
* 175238964924167385638945712569371248213489657847526139782653491496812573351794826
E9: 2,4                                  # 15 pairs
F9: 5,9,2,4,7                            # reduction candidate for 5,9
F9: 5,9 => CTR
* 15.238.64.241.7385.38.54.12.653712482134896578475261395826.34.14.68125.33.1745826
F9: 2,4,7                                # 14 pairs
* PAIR E7: 5,9 ROW 7
A7: 5,9,2,7                              # reduction candidate for 5,9
A7: 5,9 => CTR
* 1..238764.2419.385.387..912.6.371248213489657847526139.826.34714.681.5.33.19..826
A7: 2,7                                  # 21 pairs
C7: 5,9,2,7                              # reduction candidate for 5,9
C7: 5,9 => CTR
* 1.7238964.241.7385.38.4.712569371248713482659842...1372856.34714.681.5.33.1.24896
C7: 2,7                                  # 16 pairs
* PAIR E7: 5,9 COL E
E3: 5,9,4,6                              # reduction candidate for 5,9
E3: 5,9 => CTR
* 15.238.64.2416.385638.54.12.653712482134896578475261395826.34.14.681.5.33.1.45826
E3: 4,6                                  # 15 pairs
E6: 5,9,2,6                              # reduction candidate for 5,9
E6: 5,9 => CTR
* 1..238.6492416738563894571256937124871348265984259613728.65349147681.5233.1.248.6
E6: 2,6                                  # 15 pairs
* PAIR H7: 7,9 BLK 9
H8: 7,9,2                                # reduction candidate for 7,9
H8: 7,9 => SOLVED
* 175238964924167385638945712569371248213489657847526139782653491496812573351794826
H8: 2                                    # 18 pairs
H9: 7,9,2                                # reduction candidate for 7,9
H9: 7,9                                  # 18 pairs
* PAIR H7: 7,9 ROW 7
A7: 7,9,2,5                              # reduction candidate for 7,9
A7: 7,9                                  # 16 pairs
C7: 7,9,2,5                              # reduction candidate for 7,9
C7: 7,9 => CTR
* 1.5238.64.241..385.38.4..12569371248713482659842...137287653491496817523351924876
C7: 2,5                                  # 15 pairs
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-266-base-pr-000.dot
* REASONING
* DIS # F2: 6,9 => CTR => F2: 7
* DIS # E3: 6,9 => CTR => E3: 4,5
* DIS # F3: 6,9 => CTR => F3: 4,5,7
* DIS # A2: 7 => CTR => A2: 6,9
* DIS # A3: 7,9 => CTR => A3: 6
* DIS # F3: 7,9 => CTR => F3: 4,5,6
* DIS # A7: 5,9 => CTR => A7: 2,7
* DIS # C7: 5,9 => CTR => C7: 2,7
* DIS # A7: 5,9 => CTR => A7: 2,7
* DIS # C7: 5,9 => CTR => C7: 2,7
* DIS # F6: 2,9 => CTR => F6: 5,6
* DIS # F9: 2,9 => CTR => F9: 4,5,7
* DIS # E6: 5,9 => CTR => E6: 2,6
* DIS # F6: 5,9 => CTR => F6: 2,6
* DIS # D9: 5,9 => CTR => D9: 7
* DIS # C7: 7,9 => CTR => C7: 2,5
* PRF # H8: 7,9 => SOL
* DIS # D9: 5,9 => CTR => D9: 7
* PRF # E9: 5,9 => SOL
* DIS # F9: 5,9 => CTR => F9: 2,4,7
* DIS # A7: 5,9 => CTR => A7: 2,7
* DIS # C7: 5,9 => CTR => C7: 2,7
* DIS # E3: 5,9 => CTR => E3: 4,6
* DIS # E6: 5,9 => CTR => E6: 2,6
* PRF # H8: 7,9 => SOL
* DIS # C7: 7,9 => CTR => C7: 2,5
* CNT  26 HDP CHAINS /  68 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A4,A5,B8,C4,C6,D6,E2,E7,F5,G1,G3,H7,I5,I6)
* 1..238.64.241..385.38....12.6.371248.1348.65.84....13..8.6.34.14.681.5.33.1...8.6
* PAIR E2: 6,9 BLK 2
F2: 6,9,7                                # reduction candidate for 6,9
F2: 6,9 => CTR
* 1..2387647241963856387..912.6.37124821348965784756213998265347147681.5.33.1...8.6
E3: 6,9,4,5                              # reduction candidate for 6,9
E3: 6,9 => CTR
* 1..238.64.241.7385.38..4.12.6.371248.1348.65.84...613..8.6.34.14.681.5.33.1745826
* RESTART
* PAIR E2: 6,9 COL E
E6: 6,9,2,5                              # reduction candidate for 6,9
E6: 6,9 => CTR
* 1952387646241.7385.38....12.6.371248.13482659842...13728.6.34.14.68195233.1724896
E6: 2,5 => SOLVED
* 175238964924167385638945712569371248213489657847526139782653491496812573351794826
* DURATION: 0:00:05.419167  START: 11:59:51.159795  END: 11:59:56.578962 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-266-base-pr-001.dot
* REASONING
* DIS # F2: 6,9 => CTR => F2: 7
* DIS F2: 7 # E3: 6,9 => CTR => E3: 4,5
* DIS F2: 7 + E3: 4,5 # E6: 6,9 => CTR => E6: 2,5
* PRF F2: 7 + E3: 4,5 + E6: 2,5 => SOL
* STA F2: 7 + E3: 4,5 + E6: 2,5
* CNT   4 HDP CHAINS /   3 HYP OPENED

Header Info

Top 500 Minimum 17 266

solution: 175238964924167385638945712569371248213489657847526139782653491496812573351794826
info: 2139     FNBTHWY  S8.f     4125

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

Solution

position: 175238964924167385638945712569371248213489657847526139782653491496812573351794826 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:

* DIS # F2: 6,9 => CTR => F2: 7
* INC # F2: 7 => UNS
* DIS # E3: 6,9 => CTR => E3: 4,5
* INC # E3: 4,5 => UNS
* DIS # F3: 6,9 => CTR => F3: 4,5,7
* INC # F3: 4,5,7 => UNS
* INC # A2: 6,9 => UNS
* DIS # A2: 7 => CTR => A2: 6,9
* INC # E6: 6,9 => UNS
* INC # E6: 2,5 => UNS
* INC # B1: 7,9 => UNS
* INC # C1: 7,9 => UNS
* DIS # A3: 7,9 => CTR => A3: 6
* INC # A3: 6 => UNS
* INC # D3: 7,9 => UNS
* DIS # F3: 7,9 => CTR => F3: 4,5,6
* INC # F3: 4,5,6 => UNS
* DIS # A7: 5,9 => CTR => A7: 2,7
* INC # A7: 2,7 => UNS
* INC # C1: 5,9 => UNS
* DIS # C7: 5,9 => CTR => C7: 2,7
* INC # C7: 2,7 => UNS
* INC # A7: 2,7 => UNS
* DIS # A7: 5,9 => CTR => A7: 2,7
* INC # C7: 2,7 => UNS
* DIS # C7: 5,9 => CTR => C7: 2,7
* INC # E6: 2,9 => UNS
* DIS # F6: 2,9 => CTR => F6: 5,6
* INC # F6: 5,6 => UNS
* INC # F8: 2,9 => UNS
* DIS # F9: 2,9 => CTR => F9: 4,5,7
* INC # F9: 4,5,7 => UNS
* DIS # E6: 5,9 => CTR => E6: 2,6
* INC # E6: 2,6 => UNS
* DIS # F6: 5,9 => CTR => F6: 2,6
* INC # F6: 2,6 => UNS
* INC # D3: 5,9 => UNS
* DIS # D9: 5,9 => CTR => D9: 7
* INC # D9: 7 => UNS
* INC # A7: 7,9 => UNS
* DIS # C7: 7,9 => CTR => C7: 2,5
* INC # C7: 2,5 => UNS
* INC # B9: 7,9 => UNS
* INC # F8: 7,9 => UNS
* PRF # H8: 7,9 => SOL
* INC # H8: 2 => UNS
* INC # B1: 7,9 => UNS
* INC # B1: 5 => UNS
* DIS # D9: 5,9 => CTR => D9: 7
* INC # D9: 7 => UNS
* PRF # E9: 5,9 => SOL
* INC # E9: 2,4 => UNS
* DIS # F9: 5,9 => CTR => F9: 2,4,7
* INC # F9: 2,4,7 => UNS
* DIS # A7: 5,9 => CTR => A7: 2,7
* INC # A7: 2,7 => UNS
* DIS # C7: 5,9 => CTR => C7: 2,7
* INC # C7: 2,7 => UNS
* DIS # E3: 5,9 => CTR => E3: 4,6
* INC # E3: 4,6 => UNS
* DIS # E6: 5,9 => CTR => E6: 2,6
* INC # E6: 2,6 => UNS
* PRF # H8: 7,9 => SOL
* INC # H8: 2 => UNS
* INC # H9: 7,9 => UNS
* INC # A7: 7,9 => UNS
* DIS # C7: 7,9 => CTR => C7: 2,5
* INC # C7: 2,5 => UNS
* CNT  68 HDP CHAINS /  68 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* DIS # F2: 6,9 => CTR => F2: 7
* DIS F2: 7 # E3: 6,9 => CTR => E3: 4,5
* DIS F2: 7 + E3: 4,5 # E6: 6,9 => CTR => E6: 2,5
* PRF F2: 7 + E3: 4,5 + E6: 2,5 => SOL
* STA F2: 7 + E3: 4,5 + E6: 2,5
* CNT   4 HDP CHAINS /   3 HYP OPENED