Analysis of xx-top500-307-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: ...2....6.4.....5..1.......6...3...5....741..2........5..8..........3.7.......4.. initial

Autosolve

position: 7..2.1.46.4.3.7.51.1.45...76.4132..5....741..2.1.....45.784..1.4...1357.1..7254.. autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* DIS # E2: 8,9 => CTR => E2: 6
* DIS # E2: 8,9 => CTR => E2: 6
* DIS # E6: 6 => CTR => E6: 8,9
* DIS # G4: 8,9 => CTR => G4: 7
* DIS # H5: 8,9 => CTR => H5: 2,3,6
* PRF # I5: 8,9 => SOL
* DIS # B4: 7 => CTR => B4: 8,9
* PRF # H3: 8,9 => SOL
* DIS # H9: 8,9 => CTR => H9: 3,6
* DIS # B8: 8,9 => CTR => B8: 2,6
* DIS # B9: 8,9 => CTR => B9: 3,6
* DIS # I8: 8,9 => CTR => I8: 2
* PRF # I8: 2 => SOL
* DIS # B7: 6,9 => CTR => B7: 2,3
* PRF # G7: 6,9 => SOL
* DIS # G7: 2,3 => CTR => G7: 6,9
* PRF # B8: 6,9 => SOL
* DIS # B8: 2,8 => CTR => B8: 6,9
* DIS # D6: 6,9 => CTR => D6: 5
* CNT  19 HDP CHAINS /  48 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 # E2: 8,9 => CTR => E2: 6
* DIS E2: 6 # G4: 8,9 => CTR => G4: 7
* DIS E2: 6 + G4: 7 # H5: 8,9 => CTR => H5: 2,6
* PRF E2: 6 + G4: 7 + H5: 2,6 # I5: 8,9 => SOL
* STA E2: 6 + G4: 7 + H5: 2,6 + I5: 8,9
* CNT   4 HDP CHAINS /  17 HYP OPENED

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

Details

Positions

...2....6.4.....5..1.......6...3...5....741..2........5..8..........3.7.......4.. initial
7..2.1.46.4.3.7.51.1.45...76.4132..5....741..2.1.....45.784..1.4...1357.1..7254.. autosolve
785291346942367851316458297694132785853674129271589634527846913468913572139725468 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (8)
A2: 8,9
C2: 2,6
C3: 2,6
E1: 8,9
H4: 8,9
C8: 8,9
F7: 6,9
D8: 6,9

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
C2,C3: 2.. / C2 = 2  =>  9 pairs (_) / C3 = 2  =>  0 pairs (X)
H5,I5: 2.. / H5 = 2  =>  0 pairs (*) / I5 = 2  =>  0 pairs (X)
B7,B8: 2.. / B7 = 2  =>  0 pairs (*) / B8 = 2  =>  0 pairs (X)
C2,G2: 2.. / C2 = 2  =>  9 pairs (_) / G2 = 2  =>  0 pairs (X)
B8,I8: 2.. / B8 = 2  =>  0 pairs (X) / I8 = 2  =>  0 pairs (_)
H3,H5: 2.. / H3 = 2  =>  0 pairs (X) / H5 = 2  =>  0 pairs (_)
A3,A5: 3.. / A3 = 3  =>  9 pairs (_) / A5 = 3  => 12 pairs (_)
B1,C1: 5.. / B1 = 5  =>  9 pairs (_) / C1 = 5  =>  8 pairs (_)
D5,D6: 5.. / D5 = 5  =>  0 pairs (X) / D6 = 5  =>  9 pairs (_)
B6,D6: 5.. / B6 = 5  =>  0 pairs (X) / D6 = 5  =>  9 pairs (_)
C1,C5: 5.. / C1 = 5  =>  8 pairs (_) / C5 = 5  =>  9 pairs (_)
C2,C3: 6.. / C2 = 6  =>  0 pairs (X) / C3 = 6  =>  9 pairs (_)
E2,F3: 6.. / E2 = 6  =>  9 pairs (_) / F3 = 6  =>  0 pairs (X)
F7,D8: 6.. / F7 = 6  =>  0 pairs (*) / D8 = 6  =>  0 pairs (X)
G7,H9: 6.. / G7 = 6  =>  0 pairs (X) / H9 = 6  =>  0 pairs (_)
C2,E2: 6.. / C2 = 6  =>  0 pairs (X) / E2 = 6  =>  9 pairs (_)
C3,F3: 6.. / C3 = 6  =>  9 pairs (_) / F3 = 6  =>  0 pairs (X)
D5,H5: 6.. / D5 = 6  =>  0 pairs (*) / H5 = 6  =>  0 pairs (X)
B8,D8: 6.. / B8 = 6  =>  0 pairs (*) / D8 = 6  =>  0 pairs (X)
B9,H9: 6.. / B9 = 6  =>  0 pairs (X) / H9 = 6  =>  0 pairs (_)
E2,E6: 6.. / E2 = 6  =>  9 pairs (_) / E6 = 6  =>  0 pairs (X)
G6,G7: 6.. / G6 = 6  =>  0 pairs (*) / G7 = 6  =>  0 pairs (X)
B4,B6: 7.. / B4 = 7  =>  0 pairs (X) / B6 = 7  => 10 pairs (_)
G4,G6: 7.. / G4 = 7  => 10 pairs (_) / G6 = 7  =>  0 pairs (X)
B4,G4: 7.. / B4 = 7  =>  0 pairs (X) / G4 = 7  => 10 pairs (_)
B6,G6: 7.. / B6 = 7  => 10 pairs (_) / G6 = 7  =>  0 pairs (X)
E6,F6: 8.. / E6 = 8  => 11 pairs (_) / F6 = 8  => 10 pairs (_)
F3,F6: 8.. / F3 = 8  => 11 pairs (_) / F6 = 8  => 10 pairs (_)
F7,D8: 9.. / F7 = 9  =>  0 pairs (X) / D8 = 9  =>  0 pairs (_)
* DURATION: 0:00:46.298712  START: 13:28:15.220735  END: 13:29:01.519447 2017-05-04
* CP COUNT: (29)
* SOLUTION FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A2,C2,C3,C8,D8,E1,F7,H4)
* 7..2.1.46.4.3.7.51.1.45...76.4132..5....741..2.1.....45.784..1.4...1357.1..7254..
* PAIR A2: 8,9 BLK 1
B1: 8,9,3,5                              # reduction candidate for 8,9
B1: 8,9                                  # 10 pairs
C1: 8,9,3,5                              # reduction candidate for 8,9
C1: 8,9                                  # 12 pairs
A3: 8,9,3                                # reduction candidate for 8,9
A3: 8,9                                  # 12 pairs
* PAIR A2: 8,9 ROW 2
E2: 8,9,6                                # reduction candidate for 8,9
E2: 8,9 => CTR
* 7..2.1.46.463.7251.12456..76.4132..5....7412.2.1.68..45.784961.4..61357.16.7254..
E2: 6                                    #  9 pairs
G2: 8,9,2                                # reduction candidate for 8,9
G2: 8,9                                  #  9 pairs
* PAIR A2: 8,9 COL A
A5: 8,9,3                                # reduction candidate for 8,9
A5: 3                                    # 12 pairs
A5: 8,9                                  #  9 pairs
* PAIR E1: 8,9 BLK 2
E2: 8,9,6                                # reduction candidate for 8,9
E2: 8,9 => CTR
* 7..2.1.46.463.7251.12456..76.4132..5....7412.2.1.68..45.784961.4..61357.16.7254..
E2: 6                                    #  9 pairs
F3: 8,9,6                                # reduction candidate for 8,9
F3: 8,9                                  #  9 pairs
* PAIR E1: 8,9 ROW 1
B1: 8,9,3,5                              # reduction candidate for 8,9
B1: 8,9                                  # 10 pairs
C1: 8,9,3,5                              # reduction candidate for 8,9
C1: 8,9                                  # 12 pairs
G1: 8,9,3                                # reduction candidate for 8,9
G1: 8,9                                  # 12 pairs
* PAIR E1: 8,9 COL E
E6: 8,9,6                                # reduction candidate for 8,9
E6: 6 => CTR
* 7..2.1.46.463.7251.12456..76.4132..5....741..2.1.68..45.784.61.4..61357.16.7254..
E6: 8,9                                  #  9 pairs
* PAIR H4: 8,9 BLK 6
G4: 8,9,7                                # reduction candidate for 8,9
G4: 8,9 => CTR
* 7..2.1.46.4.3.7.51.1.45...7674132..5....741622.1...7345278496134..61357.1637254..
G4: 7                                    # 10 pairs
H5: 8,9,2,3,6                            # reduction candidate for 8,9
H5: 8,9 => CTR
* 7..2.1.46.4.3.7.51.1.45..276.4132..5...6741.22.15....45.784621.4...1357.1..7254..
H5: 2,3,6                                #  8 pairs
I5: 8,9,2,3                              # reduction candidate for 8,9
I5: 8,9 => SOLVED
* 785291346942367851316458297694132785853674129271589634527846913468913572139725468
I5: 2,3                                  # 10 pairs
* PAIR H4: 8,9 ROW 4
B4: 8,9,7                                # reduction candidate for 8,9
B4: 7 => CTR
* 7..2.1.46.4.3.7.51.1.45...7674132..5....741622.1...7345278496134..61357.1637254..
B4: 8,9                                  # 10 pairs
* PAIR H4: 8,9 COL H
H3: 8,9,2,3                              # reduction candidate for 8,9
H3: 8,9 => SOLVED
* 785291346942367851316458297694132785853674129271589634527846913468913572139725468
H3: 2,3                                  # 13 pairs
H9: 8,9,3,6                              # reduction candidate for 8,9
H9: 8,9 => CTR
* 7..2.1.46.4.3.7.51.1.45...76.4132..5....741622.1.....45278496134..61357.1637254..
H9: 3,6                                  #  9 pairs
* PAIR C8: 8,9 BLK 7
B8: 8,9,2,6                              # reduction candidate for 8,9
B8: 8,9 => CTR
* 7..2.1.46.4.3.7.51.1.45...76.4132..5....741..2.1.....452784..1.4..6135721637254..
B8: 2,6                                  #  9 pairs
B9: 8,9,3,6                              # reduction candidate for 8,9
B9: 8,9 => CTR
* 7..2.1.46.4.367.51.1645...76.41327.5...67412.2715..634527846.13468913572193725468
B9: 3,6                                  #  9 pairs
C9: 8,9,3                                # reduction candidate for 8,9
C9: 8,9                                  # 13 pairs
* PAIR C8: 8,9 ROW 8
I8: 8,9,2                                # reduction candidate for 8,9
I8: 8,9 => CTR
* 7..2.1.46.4.3.7.51.1.45...76.4132..5....741622.1.....45.7849.1.42.61357.1..7254..
I8: 2 => SOLVED
* 785291346942367851316458297694132785853674129271589634527846913468913572139725468
* PAIR C8: 8,9 COL C
C1: 8,9,3,5                              # reduction candidate for 8,9
C1: 8,9                                  # 12 pairs
C5: 8,9,3,5                              # reduction candidate for 8,9
C5: 8,9                                  # 10 pairs
* PAIR F7: 6,9 ROW 7
B7: 6,9,2,3                              # reduction candidate for 6,9
B7: 6,9 => CTR
* 7..2.1.46.4.3.7.51.1.45...76.4132..5....741622.1.....45.7849.1.42.61357.1..7254..
B7: 2,3                                  #  9 pairs
G7: 6,9,2,3                              # reduction candidate for 6,9
G7: 6,9 => SOLVED
* 785291346942367851316458297694132785853674129271589634527846913468913572139725468
G7: 2,3 => CTR
* 7..2.1.46.4.367.51.1645...76.41327.5...6741..2715..6345.7846.1.46.9135721..725468
* PAIR F7: 6,9 COL F
F3: 6,9,8                                # reduction candidate for 6,9
F3: 6,9                                  # 10 pairs
F6: 6,9,8                                # reduction candidate for 6,9
F6: 6,9                                  # 11 pairs
* PAIR D8: 6,9 ROW 8
B8: 6,9,2,8                              # reduction candidate for 6,9
B8: 6,9 => SOLVED
* 785291346942367851316458297694132785853674129271589634527846913468913572139725468
B8: 2,8 => CTR
* 7..2.1.46.4.3.7.51.1.45...76.4132..5....741622.1.....45.7849.1.4..61357.1..7254..
* PAIR D8: 6,9 COL D
D5: 6,9,5                                # reduction candidate for 6,9
D5: 6,9                                  #  9 pairs
D6: 6,9,5                                # reduction candidate for 6,9
D6: 6,9 => CTR
* 7..2.1.46.4.3.7.51.1.45...76.4132..5...574162251...7.45.784..1.4...1357.1..7254..
D6: 5                                    #  9 pairs
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-307-base-pr-000.dot
* REASONING
* DIS # E2: 8,9 => CTR => E2: 6
* DIS # E2: 8,9 => CTR => E2: 6
* DIS # E6: 6 => CTR => E6: 8,9
* DIS # G4: 8,9 => CTR => G4: 7
* DIS # H5: 8,9 => CTR => H5: 2,3,6
* PRF # I5: 8,9 => SOL
* DIS # B4: 7 => CTR => B4: 8,9
* PRF # H3: 8,9 => SOL
* DIS # H9: 8,9 => CTR => H9: 3,6
* DIS # B8: 8,9 => CTR => B8: 2,6
* DIS # B9: 8,9 => CTR => B9: 3,6
* DIS # I8: 8,9 => CTR => I8: 2
* PRF # I8: 2 => SOL
* DIS # B7: 6,9 => CTR => B7: 2,3
* PRF # G7: 6,9 => SOL
* DIS # G7: 2,3 => CTR => G7: 6,9
* PRF # B8: 6,9 => SOL
* DIS # B8: 2,8 => CTR => B8: 6,9
* DIS # D6: 6,9 => CTR => D6: 5
* CNT  19 HDP CHAINS /  48 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A2,C2,C3,C8,D8,E1,F7,H4)
* 7..2.1.46.4.3.7.51.1.45...76.4132..5....741..2.1.....45.784..1.4...1357.1..7254..
* PAIR A2: 8,9 BLK 1
B1: 8,9,3,5                              # reduction candidate for 8,9
B1: 8,9                                  # 10 pairs
C1: 8,9,3,5                              # reduction candidate for 8,9
C1: 8,9                                  # 12 pairs
A3: 8,9,3                                # reduction candidate for 8,9
A3: 8,9                                  # 12 pairs
* PAIR A2: 8,9 ROW 2
E2: 8,9,6                                # reduction candidate for 8,9
E2: 8,9 => CTR
* 7..2.1.46.463.7251.12456..76.4132..5....7412.2.1.68..45.784961.4..61357.16.7254..
* RESTART
* PAIR A2: 8,9 COL A
A5: 8,9,3                                # reduction candidate for 8,9
A5: 3                                    # 19 pairs
A5: 8,9                                  # 10 pairs
* PAIR RESTART
* PAIR A2: 8,9 BLK 1
B1: 8,9,3,5                              # reduction candidate for 8,9
B1: 8,9                                  # 11 pairs
C1: 8,9,3,5                              # reduction candidate for 8,9
C1: 8,9                                  # 13 pairs
A3: 8,9,3                                # reduction candidate for 8,9
A3: 8,9                                  # 19 pairs
* PAIR A2: 8,9 COL A
A5: 8,9,3                                # reduction candidate for 8,9
A5: 3                                    # 19 pairs
A5: 8,9                                  # 10 pairs
* PAIR E1: 8,9 ROW 1
B1: 8,9,3,5                              # reduction candidate for 8,9
B1: 8,9                                  # 11 pairs
C1: 8,9,3,5                              # reduction candidate for 8,9
C1: 8,9                                  # 13 pairs
G1: 8,9,3                                # reduction candidate for 8,9
G1: 8,9                                  # 19 pairs
* PAIR H4: 8,9 BLK 6
G4: 8,9,7                                # reduction candidate for 8,9
G4: 8,9 => CTR
* 7..2.1.46.42367.51.1645.2.7674132..5....741..2.1...7.45.784.61.4..61357.16.7254..
H5: 8,9,2,6                              # reduction candidate for 8,9
H5: 8,9 => CTR
* 7..2.1.46.42367.51.1645..276.41327.5...6741.22715...345.784621.4...1357.1..7254..
I5: 8,9,2                                # reduction candidate for 8,9
I5: 8,9 => SOLVED
* 785291346942367851316458297694132785853674129271589634527846913468913572139725468
* DURATION: 0:00:17.303941  START: 13:29:44.515306  END: 13:30:01.819247 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-307-base-pr-001.dot
* REASONING
* DIS # E2: 8,9 => CTR => E2: 6
* DIS E2: 6 # G4: 8,9 => CTR => G4: 7
* DIS E2: 6 + G4: 7 # H5: 8,9 => CTR => H5: 2,6
* PRF E2: 6 + G4: 7 + H5: 2,6 # I5: 8,9 => SOL
* STA E2: 6 + G4: 7 + H5: 2,6 + I5: 8,9
* CNT   4 HDP CHAINS /  17 HYP OPENED

Header Info

Top 500 Minimum 17 307

solution: 785291346942367851316458297694132785853674129271589634527846913468913572139725468
info: 2649     FNBHWY   S8.f     43281

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

Solution

position: 785291346942367851316458297694132785853674129271589634527846913468913572139725468 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: 8,9 => UNS
* INC # C1: 8,9 => UNS
* INC # A3: 8,9 => UNS
* DIS # E2: 8,9 => CTR => E2: 6
* INC # E2: 6 => UNS
* INC # G2: 8,9 => UNS
* INC # A5: 8,9 => UNS
* INC # A5: 3 => UNS
* DIS # E2: 8,9 => CTR => E2: 6
* INC # E2: 6 => UNS
* INC # F3: 8,9 => UNS
* INC # B1: 8,9 => UNS
* INC # C1: 8,9 => UNS
* INC # G1: 8,9 => UNS
* INC # E6: 8,9 => UNS
* DIS # E6: 6 => CTR => E6: 8,9
* DIS # G4: 8,9 => CTR => G4: 7
* INC # G4: 7 => UNS
* DIS # H5: 8,9 => CTR => H5: 2,3,6
* INC # H5: 2,3,6 => UNS
* PRF # I5: 8,9 => SOL
* INC # I5: 2,3 => UNS
* INC # B4: 8,9 => UNS
* DIS # B4: 7 => CTR => B4: 8,9
* PRF # H3: 8,9 => SOL
* INC # H3: 2,3 => UNS
* DIS # H9: 8,9 => CTR => H9: 3,6
* INC # H9: 3,6 => UNS
* DIS # B8: 8,9 => CTR => B8: 2,6
* INC # B8: 2,6 => UNS
* DIS # B9: 8,9 => CTR => B9: 3,6
* INC # B9: 3,6 => UNS
* INC # C9: 8,9 => UNS
* DIS # I8: 8,9 => CTR => I8: 2
* PRF # I8: 2 => SOL
* INC # C1: 8,9 => UNS
* INC # C5: 8,9 => UNS
* DIS # B7: 6,9 => CTR => B7: 2,3
* INC # B7: 2,3 => UNS
* PRF # G7: 6,9 => SOL
* DIS # G7: 2,3 => CTR => G7: 6,9
* INC # F3: 6,9 => UNS
* INC # F6: 6,9 => UNS
* PRF # B8: 6,9 => SOL
* DIS # B8: 2,8 => CTR => B8: 6,9
* INC # D5: 6,9 => UNS
* DIS # D6: 6,9 => CTR => D6: 5
* INC # D6: 5 => UNS
* CNT  48 HDP CHAINS /  48 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* INC # B1: 8,9 => UNS
* INC # C1: 8,9 => UNS
* INC # A3: 8,9 => UNS
* DIS # E2: 8,9 => CTR => E2: 6
* INC E2: 6 # A5: 8,9 => UNS
* INC E2: 6 # A5: 3 => UNS
* INC E2: 6 # B1: 8,9 => UNS
* INC E2: 6 # C1: 8,9 => UNS
* INC E2: 6 # A3: 8,9 => UNS
* INC E2: 6 # A5: 8,9 => UNS
* INC E2: 6 # A5: 3 => UNS
* INC E2: 6 # B1: 8,9 => UNS
* INC E2: 6 # C1: 8,9 => UNS
* INC E2: 6 # G1: 8,9 => UNS
* DIS E2: 6 # G4: 8,9 => CTR => G4: 7
* DIS E2: 6 + G4: 7 # H5: 8,9 => CTR => H5: 2,6
* PRF E2: 6 + G4: 7 + H5: 2,6 # I5: 8,9 => SOL
* STA E2: 6 + G4: 7 + H5: 2,6 + I5: 8,9
* CNT  17 HDP CHAINS /  17 HYP OPENED