Analysis of xx-top500-260-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: ...2...193........7........6...7.3.....46.....9.....5.....857...1.9.............. initial

Autosolve

position: ...237.193......7.7........68257.3...7.46.....9....657....857...179........7..... autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* DIS # B1: 4,5 => CTR => B1: 6
* PRF # F5: 1,9 => SOL
* DIS # F5: 3 => CTR => F5: 1,9
* DIS # F6: 1,2 => CTR => F6: 3,8
* PRF # F6: 3,8 => SOL
* DIS # E9: 4 => CTR => E9: 1,2
* DIS # I9: 1,4 => CTR => I9: 2,3,5,6,8
* PRF # F5: 1,9 => SOL
* DIS # F5: 3 => CTR => F5: 1,9
* DIS # B9: 4,6 => CTR => B9: 3,5
* DIS # C9: 4,6 => CTR => C9: 5,8
* DIS # H7: 4,6 => CTR => H7: 2,3,9
* DIS # I7: 4,6 => CTR => I7: 1,2,3
* DIS # C1: 4,6 => CTR => C1: 5,8
* DIS # E9: 2,4 => CTR => E9: 1
* PRF # E9: 1 => SOL
* CNT  16 HDP CHAINS /  47 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 # B1: 4,5 => CTR => B1: 6
* PRF B1: 6 # F5: 1,9 => SOL
* STA B1: 6 + F5: 1,9
* CNT   2 HDP CHAINS /  18 HYP OPENED

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

Details

Positions

...2...193........7........6...7.3.....46.....9.....5.....857...1.9.............. initial
...237.193......7.7........68257.3...7.46.....9....657....857...179........7..... autosolve
468237519351694278729158463682571394573469182194823657946385721217946835835712946 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (19)
C2: 1,9
C3: 1,9
E2: 5,9
E3: 5,9
G1: 4,5
A5: 1,5
C5: 3,5
A6: 1,4
C6: 3,4
F4: 1,9
E6: 1,2
H4: 4,9
I4: 1,4
G5: 1,9
H5: 2,8
I5: 2,8
C7: 4,6
E8: 2,4
G9: 1,9

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
C2,C3: 1.. / C2 = 1  => 17 pairs (_) / C3 = 1  => 17 pairs (_)
A5,A6: 1.. / A5 = 1  =>  0 pairs (X) / A6 = 1  =>  0 pairs (_)
I4,G5: 1.. / I4 = 1  =>  0 pairs (X) / G5 = 1  =>  0 pairs (_)
F4,I4: 1.. / F4 = 1  =>  0 pairs (*) / I4 = 1  =>  0 pairs (X)
D7,I7: 1.. / D7 = 1  =>  0 pairs (X) / I7 = 1  =>  0 pairs (_)
E6,E9: 1.. / E6 = 1  =>  0 pairs (X) / E9 = 1  =>  0 pairs (_)
G5,G9: 1.. / G5 = 1  =>  0 pairs (*) / G9 = 1  =>  0 pairs (X)
B2,B3: 2.. / B2 = 2  => 20 pairs (_) / B3 = 2  => 20 pairs (_)
E6,F6: 2.. / E6 = 2  =>  0 pairs (*) / F6 = 2  =>  0 pairs (X)
H5,I5: 2.. / H5 = 2  => 17 pairs (_) / I5 = 2  => 19 pairs (_)
H3,I3: 3.. / H3 = 3  => 19 pairs (_) / I3 = 3  => 19 pairs (_)
C5,C6: 3.. / C5 = 3  =>  0 pairs (*) / C6 = 3  =>  0 pairs (X)
B7,B9: 3.. / B7 = 3  =>  0 pairs (X) / B9 = 3  => 24 pairs (_)
C5,F5: 3.. / C5 = 3  =>  0 pairs (*) / F5 = 3  =>  0 pairs (X)
D6,D7: 3.. / D6 = 3  =>  0 pairs (X) / D7 = 3  =>  0 pairs (_)
F2,F3: 4.. / F2 = 4  => 20 pairs (_) / F3 = 4  => 20 pairs (_)
A6,C6: 4.. / A6 = 4  =>  0 pairs (X) / C6 = 4  =>  0 pairs (_)
H4,I4: 4.. / H4 = 4  =>  0 pairs (X) / I4 = 4  =>  0 pairs (_)
E8,E9: 4.. / E8 = 4  => 19 pairs (_) / E9 = 4  =>  0 pairs (X)
E2,E3: 5.. / E2 = 5  => 17 pairs (_) / E3 = 5  => 17 pairs (_)
A5,C5: 5.. / A5 = 5  =>  0 pairs (*) / C5 = 5  =>  0 pairs (X)
B1,C1: 6.. / B1 = 6  => 20 pairs (_) / C1 = 6  =>  0 pairs (X)
A1,C1: 8.. / A1 = 8  => 19 pairs (_) / C1 = 8  => 23 pairs (_)
D6,F6: 8.. / D6 = 8  =>  0 pairs (*) / F6 = 8  =>  0 pairs (X)
H5,I5: 8.. / H5 = 8  => 19 pairs (_) / I5 = 8  => 17 pairs (_)
C1,C9: 8.. / C1 = 8  => 23 pairs (_) / C9 = 8  => 19 pairs (_)
C2,C3: 9.. / C2 = 9  => 17 pairs (_) / C3 = 9  => 17 pairs (_)
E2,E3: 9.. / E2 = 9  => 17 pairs (_) / E3 = 9  => 17 pairs (_)
F4,F5: 9.. / F4 = 9  =>  0 pairs (X) / F5 = 9  =>  0 pairs (_)
H4,G5: 9.. / H4 = 9  =>  0 pairs (*) / G5 = 9  =>  0 pairs (X)
A7,A9: 9.. / A7 = 9  => 19 pairs (_) / A9 = 9  =>  0 pairs (X)
C2,E2: 9.. / C2 = 9  => 17 pairs (_) / E2 = 9  => 17 pairs (_)
C3,E3: 9.. / C3 = 9  => 17 pairs (_) / E3 = 9  => 17 pairs (_)
F4,H4: 9.. / F4 = 9  =>  0 pairs (X) / H4 = 9  =>  0 pairs (_)
F5,G5: 9.. / F5 = 9  =>  0 pairs (*) / G5 = 9  =>  0 pairs (X)
A7,H7: 9.. / A7 = 9  => 19 pairs (_) / H7 = 9  =>  0 pairs (X)
G5,G9: 9.. / G5 = 9  =>  0 pairs (X) / G9 = 9  =>  0 pairs (_)
* DURATION: 0:01:17.540674  START: 11:41:50.022632  END: 11:43:07.563306 2017-05-04
* CP COUNT: (37)
* SOLUTION FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A5,A6,C2,C3,C5,C6,C7,E2,E3,E6,E8,F4,G1,G5,G9,H4,H5,I4,I5)
* ...237.193......7.7........68257.3...7.46.....9....657....857...179........7.....
* PAIR G1: 4,5 BLK 3
G2: 4,5,2,8                              # reduction candidate for 4,5
G2: 4,5                                  # 22 pairs
I2: 4,5,2,6,8                            # reduction candidate for 4,5
I2: 4,5                                  # 26 pairs
G3: 4,5,2,8                              # reduction candidate for 4,5
G3: 4,5                                  # 22 pairs
I3: 4,5,2,3,6,8                          # reduction candidate for 4,5
I3: 4,5                                  # 24 pairs
* PAIR G1: 4,5 ROW 1
A1: 4,5,8                                # reduction candidate for 4,5
A1: 4,5                                  # 23 pairs
B1: 4,5,6                                # reduction candidate for 4,5
B1: 4,5 => CTR
* 8.6237.193......7.7........68257.3...754639..493...657..43857.1.179.......87.....
B1: 6                                    # 20 pairs
C1: 4,5,6,8                              # reduction candidate for 4,5
C1: 4,5                                  # 21 pairs
* PAIR G1: 4,5 COL G
G8: 4,5,2,8                              # reduction candidate for 4,5
G8: 4,5                                  # 22 pairs
G8: 2,8                                  # 20 pairs
* PAIR F4: 1,9 BLK 5
F5: 1,9,3                                # reduction candidate for 1,9
F5: 1,9 => SOLVED
* 468237519351694278729158463682571394573469182194823657946385721217946835835712946
F5: 3 => CTR
* ...237.193......7.7........6825793411754639..493...657....857...179........7.....
* PAIR E6: 1,2 BLK 5
F6: 1,2,3,8                              # reduction candidate for 1,2
F6: 1,2 => CTR
* ...237.193......7.7........68257.3...7.46.....9.8..657...3857.1.179......3.7..9..
F6: 3,8 => SOLVED
* 468237519351694278729158463682571394573469182194823657946385721217946835835712946
* PAIR E6: 1,2 COL E
E9: 1,2,4                                # reduction candidate for 1,2
E9: 4 => CTR
* ...237.193......7.7........6825793411754639..493812657....857...1792.......74....
E9: 1,2                                  # 19 pairs
* PAIR H4: 4,9 COL H
H7: 4,9,2,3,6                            # reduction candidate for 4,9
H7: 4,9                                  # 20 pairs
H9: 4,9,2,3,6,8                          # reduction candidate for 4,9
H9: 4,9                                  # 20 pairs
* PAIR I4: 1,4 COL I
I7: 1,4,2,3,6                            # reduction candidate for 1,4
I7: 1,4                                  # 22 pairs
I9: 1,4,2,3,5,6,8                        # reduction candidate for 1,4
I9: 1,4 => CTR
* ...237.193......7.7........68257.3...7.46.....9.31.657...1857...179........7.....
I9: 2,3,5,6,8                            # 19 pairs
* PAIR G5: 1,9 ROW 5
F5: 1,9,3                                # reduction candidate for 1,9
F5: 1,9 => SOLVED
* 468237519351694278729158463682571394573469182194823657946385721217946835835712946
F5: 3 => CTR
* ...237.193......7.7........6825793411754639..493...657....857...179........7.....
* PAIR H5: 2,8 COL H
H3: 2,8,3,4,6                            # reduction candidate for 2,8
H3: 2,8                                  # 24 pairs
H8: 2,8,3,4,6                            # reduction candidate for 2,8
H8: 2,8                                  # 22 pairs
H9: 2,8,3,4,6,9                          # reduction candidate for 2,8
H9: 2,8                                  # 20 pairs
* PAIR I5: 2,8 COL I
I2: 2,8,4,5,6                            # reduction candidate for 2,8
I2: 2,8                                  # 26 pairs
I3: 2,8,3,4,5,6                          # reduction candidate for 2,8
I3: 2,8                                  # 24 pairs
I8: 2,8,3,4,5,6                          # reduction candidate for 2,8
I8: 2,8                                  # 24 pairs
I9: 2,8,1,3,4,5,6                        # reduction candidate for 2,8
I9: 2,8                                  # 22 pairs
* PAIR C7: 4,6 BLK 7
B7: 4,6,3                                # reduction candidate for 4,6
B7: 4,6                                  # 24 pairs
B9: 4,6,3,5                              # reduction candidate for 4,6
B9: 4,6 => CTR
* ...237.193......7.7........68257.3...7346.....94328657.361857...1794.......7.....
B9: 3,5                                  # 20 pairs
C9: 4,6,5,8                              # reduction candidate for 4,6
C9: 4,6 => CTR
* ..8237.193......7.7........68257.3...754639...93...657...3857.1.179........7.....
C9: 5,8                                  # 20 pairs
* PAIR C7: 4,6 ROW 7
H7: 4,6,2,3,9                            # reduction candidate for 4,6
H7: 4,6 => CTR
* ...237.193......7.7........68257.3...7.46..28.9.31.6579..1857.2.179........7.....
H7: 2,3,9                                # 19 pairs
I7: 4,6,1,2,3                            # reduction candidate for 4,6
I7: 4,6 => CTR
* ...237.193......7.7........68257.3...7.46.....9.31.657...1857...179........7.....
I7: 1,2,3                                # 19 pairs
* PAIR C7: 4,6 COL C
C1: 4,6,5,8                              # reduction candidate for 4,6
C1: 4,6 => CTR
* 8..237.193......7.7........68257.3...754639...93...657...3857.1.179.......87.....
C1: 5,8                                  # 21 pairs
* PAIR E8: 2,4 BLK 8
E9: 2,4,1                                # reduction candidate for 2,4
E9: 2,4 => CTR
* ...237.193......7.7........6825793411754639..493812657....857...179........7.....
E9: 1 => SOLVED
* 468237519351694278729158463682571394573469182194823657946385721217946835835712946
* PAIR E8: 2,4 ROW 8
A8: 2,4,5,8                              # reduction candidate for 2,4
A8: 2,4                                  # 22 pairs
G8: 2,4,5,8                              # reduction candidate for 2,4
G8: 2,4                                  # 24 pairs
H8: 2,4,3,6,8                            # reduction candidate for 2,4
H8: 2,4                                  # 26 pairs
I8: 2,4,3,5,6,8                          # reduction candidate for 2,4
I8: 2,4                                  # 26 pairs
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-260-base-pr-000.dot
* REASONING
* DIS # B1: 4,5 => CTR => B1: 6
* PRF # F5: 1,9 => SOL
* DIS # F5: 3 => CTR => F5: 1,9
* DIS # F6: 1,2 => CTR => F6: 3,8
* PRF # F6: 3,8 => SOL
* DIS # E9: 4 => CTR => E9: 1,2
* DIS # I9: 1,4 => CTR => I9: 2,3,5,6,8
* PRF # F5: 1,9 => SOL
* DIS # F5: 3 => CTR => F5: 1,9
* DIS # B9: 4,6 => CTR => B9: 3,5
* DIS # C9: 4,6 => CTR => C9: 5,8
* DIS # H7: 4,6 => CTR => H7: 2,3,9
* DIS # I7: 4,6 => CTR => I7: 1,2,3
* DIS # C1: 4,6 => CTR => C1: 5,8
* DIS # E9: 2,4 => CTR => E9: 1
* PRF # E9: 1 => SOL
* CNT  16 HDP CHAINS /  47 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A5,A6,C2,C3,C5,C6,C7,E2,E3,E6,E8,F4,G1,G5,G9,H4,H5,I4,I5)
* ...237.193......7.7........68257.3...7.46.....9....657....857...179........7.....
* PAIR G1: 4,5 BLK 3
G2: 4,5,2,8                              # reduction candidate for 4,5
G2: 4,5                                  # 22 pairs
I2: 4,5,2,6,8                            # reduction candidate for 4,5
I2: 4,5                                  # 26 pairs
G3: 4,5,2,8                              # reduction candidate for 4,5
G3: 4,5                                  # 22 pairs
I3: 4,5,2,3,6,8                          # reduction candidate for 4,5
I3: 4,5                                  # 24 pairs
* PAIR G1: 4,5 ROW 1
A1: 4,5,8                                # reduction candidate for 4,5
A1: 4,5                                  # 23 pairs
B1: 4,5,6                                # reduction candidate for 4,5
B1: 4,5 => CTR
* 8.6237.193......7.7........68257.3...754639..493...657..43857.1.179.......87.....
C1: 4,5,8                                # reduction candidate for 4,5
C1: 4,5                                  # 21 pairs
* PAIR G1: 4,5 COL G
G8: 4,5,2,8                              # reduction candidate for 4,5
G8: 4,5                                  # 23 pairs
G8: 2,8                                  # 21 pairs
* PAIR RESTART
* PAIR G1: 4,5 BLK 3
G2: 4,5,2,8                              # reduction candidate for 4,5
G2: 4,5                                  # 23 pairs
I2: 4,5,2,6,8                            # reduction candidate for 4,5
I2: 4,5                                  # 27 pairs
G3: 4,5,2,8                              # reduction candidate for 4,5
G3: 4,5                                  # 23 pairs
I3: 4,5,2,3,6,8                          # reduction candidate for 4,5
I3: 4,5                                  # 25 pairs
* PAIR G1: 4,5 ROW 1
A1: 4,5,8                                # reduction candidate for 4,5
A1: 4,5                                  # 23 pairs
C1: 4,5,8                                # reduction candidate for 4,5
C1: 4,5                                  # 21 pairs
* PAIR G1: 4,5 COL G
G8: 4,5,2,8                              # reduction candidate for 4,5
G8: 4,5                                  # 23 pairs
G8: 2,8                                  # 21 pairs
* PAIR F4: 1,9 BLK 5
F5: 1,9,3                                # reduction candidate for 1,9
F5: 1,9 => SOLVED
* 468237519351694278729158463682571394573469182194823657946385721217946835835712946
* DURATION: 0:00:20.981013  START: 11:44:00.356370  END: 11:44:21.337383 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-260-base-pr-001.dot
* REASONING
* DIS # B1: 4,5 => CTR => B1: 6
* PRF B1: 6 # F5: 1,9 => SOL
* STA B1: 6 + F5: 1,9
* CNT   2 HDP CHAINS /  18 HYP OPENED

Header Info

Top 500 Minimum 17 260

solution: 468237519351694278729158463682571394573469182194823657946385721217946835835712946
info: 2089     FNBTHWY  S8.f     41036

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

Solution

position: 468237519351694278729158463682571394573469182194823657946385721217946835835712946 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 # G2: 4,5 => UNS
* INC # I2: 4,5 => UNS
* INC # G3: 4,5 => UNS
* INC # I3: 4,5 => UNS
* INC # A1: 4,5 => UNS
* DIS # B1: 4,5 => CTR => B1: 6
* INC # B1: 6 => UNS
* INC # C1: 4,5 => UNS
* INC # G8: 4,5 => UNS
* INC # G8: 2,8 => UNS
* PRF # F5: 1,9 => SOL
* DIS # F5: 3 => CTR => F5: 1,9
* DIS # F6: 1,2 => CTR => F6: 3,8
* PRF # F6: 3,8 => SOL
* INC # E9: 1,2 => UNS
* DIS # E9: 4 => CTR => E9: 1,2
* INC # H7: 4,9 => UNS
* INC # H9: 4,9 => UNS
* INC # I7: 1,4 => UNS
* DIS # I9: 1,4 => CTR => I9: 2,3,5,6,8
* INC # I9: 2,3,5,6,8 => UNS
* PRF # F5: 1,9 => SOL
* DIS # F5: 3 => CTR => F5: 1,9
* INC # H3: 2,8 => UNS
* INC # H8: 2,8 => UNS
* INC # H9: 2,8 => UNS
* INC # I2: 2,8 => UNS
* INC # I3: 2,8 => UNS
* INC # I8: 2,8 => UNS
* INC # I9: 2,8 => UNS
* INC # B7: 4,6 => UNS
* DIS # B9: 4,6 => CTR => B9: 3,5
* INC # B9: 3,5 => UNS
* DIS # C9: 4,6 => CTR => C9: 5,8
* INC # C9: 5,8 => UNS
* DIS # H7: 4,6 => CTR => H7: 2,3,9
* INC # H7: 2,3,9 => UNS
* DIS # I7: 4,6 => CTR => I7: 1,2,3
* INC # I7: 1,2,3 => UNS
* DIS # C1: 4,6 => CTR => C1: 5,8
* INC # C1: 5,8 => UNS
* DIS # E9: 2,4 => CTR => E9: 1
* PRF # E9: 1 => SOL
* INC # A8: 2,4 => UNS
* INC # G8: 2,4 => UNS
* INC # H8: 2,4 => UNS
* INC # I8: 2,4 => UNS
* CNT  47 HDP CHAINS /  47 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* INC # G2: 4,5 => UNS
* INC # I2: 4,5 => UNS
* INC # G3: 4,5 => UNS
* INC # I3: 4,5 => UNS
* INC # A1: 4,5 => UNS
* DIS # B1: 4,5 => CTR => B1: 6
* INC B1: 6 # C1: 4,5 => UNS
* INC B1: 6 # G8: 4,5 => UNS
* INC B1: 6 # G8: 2,8 => UNS
* INC B1: 6 # G2: 4,5 => UNS
* INC B1: 6 # I2: 4,5 => UNS
* INC B1: 6 # G3: 4,5 => UNS
* INC B1: 6 # I3: 4,5 => UNS
* INC B1: 6 # A1: 4,5 => UNS
* INC B1: 6 # C1: 4,5 => UNS
* INC B1: 6 # G8: 4,5 => UNS
* INC B1: 6 # G8: 2,8 => UNS
* PRF B1: 6 # F5: 1,9 => SOL
* STA B1: 6 + F5: 1,9
* CNT  18 HDP CHAINS /  18 HYP OPENED