Analysis of xx-top500-410-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: 5...2.8...6...1............3.......62...8.......5...4..416......7....9........2.. initial

Autosolve

position: 51.4268..76...142.42....6..3942175862563841..187569342.416.27...721..9...35..82.. autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* PRF # E3: 3,5 => SOL
* DIS # I3: 3,5 => CTR => I3: 1,9
* PRF # H1: 3 => SOL
* DIS # E8: 3,5 => CTR => E8: 4
* DIS # H8: 3,5 => CTR => H8: 6
* DIS # E9: 4 => CTR => E9: 7,9
* DIS # I7: 3,5 => CTR => I7: 8
* DIS # H8: 3,5 => CTR => H8: 6
* DIS # E7: 9 => CTR => E7: 3,5
* CNT   9 HDP CHAINS /  37 HYP OPENED

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

Pair Reduction

Pair Reduction

The following important HDP chains were detected:

* PRF # E3: 3,5 => SOL
* STA E3: 3,5
* CNT   1 HDP CHAINS /  10 HYP OPENED

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

Details

Positions

5...2.8...6...1............3.......62...8.......5...4..416......7....9........2.. initial
51.4268..76...142.42....6..3942175862563841..187569342.416.27...721..9...35..82.. autosolve
519426837763891425428753691394217586256384179187569342941632758872145963635978214 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (13)
C1: 3,9
D2: 8,9
F3: 3,5
H5: 7,9
I5: 7,9
A7: 8,9
A8: 6,8
A9: 6,9
F8: 3,5
D9: 7,9
H7: 3,5
H9: 1,6
I9: 1,4

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
H3,I3: 1.. / H3 = 1  =>  0 pairs (X) / I3 = 1  => 11 pairs (_)
H9,I9: 1.. / H9 = 1  => 11 pairs (_) / I9 = 1  =>  0 pairs (X)
H3,H9: 1.. / H3 = 1  =>  0 pairs (X) / H9 = 1  => 11 pairs (_)
I3,I9: 1.. / I3 = 1  => 11 pairs (_) / I9 = 1  =>  0 pairs (X)
F3,F8: 3.. / F3 = 3  => 16 pairs (_) / F8 = 3  => 17 pairs (_)
E8,E9: 4.. / E8 = 4  => 11 pairs (_) / E9 = 4  =>  0 pairs (X)
I8,I9: 4.. / I8 = 4  =>  0 pairs (X) / I9 = 4  => 11 pairs (_)
E8,I8: 4.. / E8 = 4  => 11 pairs (_) / I8 = 4  =>  0 pairs (X)
E9,I9: 4.. / E9 = 4  =>  0 pairs (X) / I9 = 4  => 11 pairs (_)
E2,I2: 5.. / E2 = 5  => 22 pairs (_) / I2 = 5  => 15 pairs (_)
F3,F8: 5.. / F3 = 5  => 17 pairs (_) / F8 = 5  => 16 pairs (_)
A8,A9: 6.. / A8 = 6  =>  0 pairs (X) / A9 = 6  => 11 pairs (_)
H8,H9: 6.. / H8 = 6  => 11 pairs (_) / H9 = 6  =>  0 pairs (X)
A8,H8: 6.. / A8 = 6  =>  0 pairs (X) / H8 = 6  => 11 pairs (_)
A9,H9: 6.. / A9 = 6  => 11 pairs (_) / H9 = 6  =>  0 pairs (X)
D3,E3: 7.. / D3 = 7  =>  9 pairs (_) / E3 = 7  => 15 pairs (_)
H1,I1: 7.. / H1 = 7  => 12 pairs (_) / I1 = 7  => 13 pairs (_)
H5,I5: 7.. / H5 = 7  => 13 pairs (_) / I5 = 7  => 12 pairs (_)
D9,E9: 7.. / D9 = 7  => 15 pairs (_) / E9 = 7  =>  9 pairs (_)
D3,D9: 7.. / D3 = 7  =>  9 pairs (_) / D9 = 7  => 15 pairs (_)
E3,E9: 7.. / E3 = 7  => 15 pairs (_) / E9 = 7  =>  9 pairs (_)
H1,H5: 7.. / H1 = 7  => 12 pairs (_) / H5 = 7  => 13 pairs (_)
I1,I5: 7.. / I1 = 7  => 13 pairs (_) / I5 = 7  => 12 pairs (_)
C2,C3: 8.. / C2 = 8  => 15 pairs (_) / C3 = 8  => 14 pairs (_)
D2,D3: 8.. / D2 = 8  => 14 pairs (_) / D3 = 8  => 15 pairs (_)
A7,A8: 8.. / A7 = 8  =>  0 pairs (X) / A8 = 8  => 11 pairs (_)
I7,I8: 8.. / I7 = 8  => 11 pairs (_) / I8 = 8  =>  0 pairs (X)
C2,D2: 8.. / C2 = 8  => 15 pairs (_) / D2 = 8  => 14 pairs (_)
C3,D3: 8.. / C3 = 8  => 14 pairs (_) / D3 = 8  => 15 pairs (_)
A7,I7: 8.. / A7 = 8  =>  0 pairs (X) / I7 = 8  => 11 pairs (_)
A8,I8: 8.. / A8 = 8  => 11 pairs (_) / I8 = 8  =>  0 pairs (X)
H5,I5: 9.. / H5 = 9  => 12 pairs (_) / I5 = 9  => 13 pairs (_)
A7,A9: 9.. / A7 = 9  => 11 pairs (_) / A9 = 9  =>  0 pairs (X)
A7,E7: 9.. / A7 = 9  => 11 pairs (_) / E7 = 9  =>  0 pairs (X)
* DURATION: 0:00:57.279415  START: 16:49:48.082247  END: 16:50:45.361662 2017-05-04
* CP COUNT: (34)
* CLUE FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A7,A8,A9,C1,D2,D9,F3,F8,H5,H7,H9,I5,I9)
* 51.4268..76...142.42....6..3942175862563841..187569342.416.27...721..9...35..82..
* PAIR C1: 3,9 BLK 1
C2: 3,9,8                                # reduction candidate for 3,9
C2: 3,9                                  # 14 pairs
C3: 3,9,8                                # reduction candidate for 3,9
C3: 3,9                                  # 15 pairs
* PAIR C1: 3,9 ROW 1
H1: 3,9,7                                # reduction candidate for 3,9
H1: 3,9                                  # 13 pairs
I1: 3,9,7                                # reduction candidate for 3,9
I1: 3,9                                  # 12 pairs
* PAIR D2: 8,9 BLK 2
D3: 8,9,7                                # reduction candidate for 8,9
D3: 8,9                                  # 15 pairs
D3: 7                                    #  9 pairs
* PAIR D2: 8,9 ROW 2
C2: 8,9,3                                # reduction candidate for 8,9
C2: 8,9                                  # 17 pairs
C2: 3                                    # 16 pairs
* PAIR F3: 3,5 BLK 2
E2: 3,5,9                                # reduction candidate for 3,5
E2: 3,5                                  # 15 pairs
E3: 3,5,7,9                              # reduction candidate for 3,5
E3: 3,5 => SOLVED
* 519426837763891425428753691394217586256384179187569342941632758872145963635978214
E3: 7,9                                  # 15 pairs
* PAIR F3: 3,5 ROW 3
H3: 3,5,1,9                              # reduction candidate for 3,5
H3: 3,5                                  # 16 pairs
I3: 3,5,1,9                              # reduction candidate for 3,5
I3: 3,5 => CTR
* 51.4268..76...142.42....61.3942175862563841..187569342.416.27..6721..9...35..8261
I3: 1,9                                  # 14 pairs
* PAIR H5: 7,9 COL H
H1: 7,9,3                                # reduction candidate for 7,9
H1: 3 => SOLVED
* 519426837763891425428753691394217586256384179187569342941632758872145963635978214
H1: 7,9                                  # 14 pairs
* PAIR I5: 7,9 COL I
I1: 7,9,3                                # reduction candidate for 7,9
I1: 7,9                                  # 15 pairs
I1: 3                                    # 15 pairs
* PAIR F8: 3,5 BLK 8
E7: 3,5,9                                # reduction candidate for 3,5
E7: 3,5                                  # 11 pairs
E8: 3,5,4                                # reduction candidate for 3,5
E8: 3,5 => CTR
* 51.4268..76...142.42..7.61.3942175862563841..187569342.416.27.88721..964.35.482.1
E8: 4                                    # 11 pairs
* PAIR F8: 3,5 ROW 8
H8: 3,5,6                                # reduction candidate for 3,5
H8: 3,5 => CTR
* 51.4268..76...142.42....6..3942175862563841..187569342.416.27..6721..9.8935748261
H8: 6                                    # 11 pairs
I8: 3,5,4,8                              # reduction candidate for 3,5
I8: 3,5                                  # 11 pairs
* PAIR D9: 7,9 BLK 8
E9: 7,9,4                                # reduction candidate for 7,9
E9: 4 => CTR
* 51.4268..76...142.42..7.61.3942175862563841..187569342.416927...721..9.4935748261
E9: 7,9                                  # 11 pairs
* PAIR D9: 7,9 COL D
D3: 7,9,8                                # reduction candidate for 7,9
D3: 8                                    # 15 pairs
D3: 7,9                                  # 14 pairs
* PAIR H7: 3,5 BLK 9
I7: 3,5,8                                # reduction candidate for 3,5
I7: 3,5 => CTR
* 51.4268..76...142.42....6..3942175862563841..1875693428416927..6721..9.8935748261
I7: 8                                    # 11 pairs
H8: 3,5,6                                # reduction candidate for 3,5
H8: 3,5 => CTR
* 51.4268..76...142.42....6..3942175862563841..187569342.416.27..6721..9.8935748261
H8: 6                                    # 11 pairs
I8: 3,5,4,8                              # reduction candidate for 3,5
I8: 3,5                                  # 11 pairs
* PAIR H7: 3,5 ROW 7
E7: 3,5,9                                # reduction candidate for 3,5
E7: 9 => CTR
* 51.4268..76...142.42..7.61.3942175862563841..1875693428416927..6721..9..935748261
E7: 3,5                                  # 11 pairs
* PAIR H7: 3,5 COL H
H3: 3,5,1,9                              # reduction candidate for 3,5
H3: 3,5                                  # 16 pairs
H3: 1,9                                  # 15 pairs
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-410-base-pr-000.dot
* REASONING
* PRF # E3: 3,5 => SOL
* DIS # I3: 3,5 => CTR => I3: 1,9
* PRF # H1: 3 => SOL
* DIS # E8: 3,5 => CTR => E8: 4
* DIS # H8: 3,5 => CTR => H8: 6
* DIS # E9: 4 => CTR => E9: 7,9
* DIS # I7: 3,5 => CTR => I7: 8
* DIS # H8: 3,5 => CTR => H8: 6
* DIS # E7: 9 => CTR => E7: 3,5
* CNT   9 HDP CHAINS /  37 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A7,A8,A9,C1,D2,D9,F3,F8,H5,H7,H9,I5,I9)
* 51.4268..76...142.42....6..3942175862563841..187569342.416.27...721..9...35..82..
* PAIR C1: 3,9 BLK 1
C2: 3,9,8                                # reduction candidate for 3,9
C2: 3,9                                  # 14 pairs
C3: 3,9,8                                # reduction candidate for 3,9
C3: 3,9                                  # 15 pairs
* PAIR C1: 3,9 ROW 1
H1: 3,9,7                                # reduction candidate for 3,9
H1: 3,9                                  # 13 pairs
I1: 3,9,7                                # reduction candidate for 3,9
I1: 3,9                                  # 12 pairs
* PAIR D2: 8,9 BLK 2
D3: 8,9,7                                # reduction candidate for 8,9
D3: 8,9                                  # 15 pairs
D3: 7                                    #  9 pairs
* PAIR D2: 8,9 ROW 2
C2: 8,9,3                                # reduction candidate for 8,9
C2: 8,9                                  # 17 pairs
C2: 3                                    # 16 pairs
* PAIR F3: 3,5 BLK 2
E2: 3,5,9                                # reduction candidate for 3,5
E2: 3,5                                  # 15 pairs
E3: 3,5,7,9                              # reduction candidate for 3,5
E3: 3,5 => SOLVED
* 519426837763891425428753691394217586256384179187569342941632758872145963635978214
* DURATION: 0:00:10.032555  START: 16:51:20.291086  END: 16:51:30.323641 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-410-base-pr-001.dot
* REASONING
* PRF # E3: 3,5 => SOL
* STA E3: 3,5
* CNT   1 HDP CHAINS /  10 HYP OPENED

Header Info

Top 500 Minimum 17 410

solution: 519426837763891425428753691394217586256384179187569342941632758872145963635978214
info: 95021    FNBXK    S8.f     44397

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

Solution

position: 519426837763891425428753691394217586256384179187569342941632758872145963635978214 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 # C2: 3,9 => UNS
* INC # C3: 3,9 => UNS
* INC # H1: 3,9 => UNS
* INC # I1: 3,9 => UNS
* INC # D3: 8,9 => UNS
* INC # D3: 7 => UNS
* INC # C2: 8,9 => UNS
* INC # C2: 3 => UNS
* INC # E2: 3,5 => UNS
* PRF # E3: 3,5 => SOL
* INC # E3: 7,9 => UNS
* INC # H3: 3,5 => UNS
* DIS # I3: 3,5 => CTR => I3: 1,9
* INC # I3: 1,9 => UNS
* INC # H1: 7,9 => UNS
* PRF # H1: 3 => SOL
* INC # I1: 7,9 => UNS
* INC # I1: 3 => UNS
* INC # E7: 3,5 => UNS
* DIS # E8: 3,5 => CTR => E8: 4
* INC # E8: 4 => UNS
* DIS # H8: 3,5 => CTR => H8: 6
* INC # H8: 6 => UNS
* INC # I8: 3,5 => UNS
* INC # E9: 7,9 => UNS
* DIS # E9: 4 => CTR => E9: 7,9
* INC # D3: 7,9 => UNS
* INC # D3: 8 => UNS
* DIS # I7: 3,5 => CTR => I7: 8
* INC # I7: 8 => UNS
* DIS # H8: 3,5 => CTR => H8: 6
* INC # H8: 6 => UNS
* INC # I8: 3,5 => UNS
* INC # E7: 3,5 => UNS
* DIS # E7: 9 => CTR => E7: 3,5
* INC # H3: 3,5 => UNS
* INC # H3: 1,9 => UNS
* CNT  37 HDP CHAINS /  37 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* INC # C2: 3,9 => UNS
* INC # C3: 3,9 => UNS
* INC # H1: 3,9 => UNS
* INC # I1: 3,9 => UNS
* INC # D3: 8,9 => UNS
* INC # D3: 7 => UNS
* INC # C2: 8,9 => UNS
* INC # C2: 3 => UNS
* INC # E2: 3,5 => UNS
* PRF # E3: 3,5 => SOL
* STA E3: 3,5
* CNT  10 HDP CHAINS /  10 HYP OPENED