Analysis of xx-top500-192-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: 3.5.....8....21...............4...5379..6..............2....61.4..3...........2.. initial

Autosolve

position: 3.56...2864..213.5....354.....4...5379.563.425342......23.5.61.4..3.258..571.623. autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* DIS # B3: 1,7 => CTR => B3: 8
* PRF # B3: 8 => SOL
* DIS # G1: 9 => CTR => G1: 1,7
* DIS # C3: 8,9 => CTR => C3: 1,2
* PRF # C3: 1,2 => SOL
* DIS # D2: 7 => CTR => D2: 8,9
* PRF # C3: 1,2 => SOL
* DIS # C3: 8,9 => CTR => C3: 1,2
* DIS # G1: 7,9 => CTR => G1: 1
* PRF # G1: 1 => SOL
* PRF # H3: 7,9 => SOL
* DIS # H3: 6 => CTR => H3: 7,9
* DIS # D2: 7,9 => CTR => D2: 8
* DIS # H6: 7,9 => CTR => H6: 6
* PRF # H6: 6 => SOL
* DIS # C4: 1,2 => CTR => C4: 6,8
* PRF # C4: 6,8 => SOL
* DIS # B4: 1,8 => CTR => B4: 6
* PRF # B4: 6 => SOL
* PRF # C4: 1,8 => SOL
* DIS # C3: 1,8 => CTR => C3: 2,9
* DIS # G4: 1,8 => CTR => G4: 7,9
* DIS # G6: 1,8 => CTR => G6: 7,9
* PRF # B4: 1,6 => SOL
* DIS # B4: 8 => CTR => B4: 1,6
* DIS # C4: 1,6 => CTR => C4: 2,8
* PRF # C4: 2,8 => SOL
* DIS # I7: 4 => CTR => I7: 7,9
* DIS # D2: 7,9 => CTR => D2: 8
* DIS # E1: 7,9 => CTR => E1: 4
* DIS # E4: 7,9 => CTR => E4: 1,8
* PRF # E6: 7,9 => SOL
* DIS # I7: 4 => CTR => I7: 7,9
* DIS # I7: 4,9 => CTR => I7: 7
* CNT  34 HDP CHAINS /  49 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 # B3: 1,7 => CTR => B3: 8
* PRF B3: 8 => SOL
* STA B3: 8
* CNT   2 HDP CHAINS /   1 HYP OPENED

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

Details

Positions

3.5.....8....21...............4...5379..6..............2....61.4..3...........2.. initial
3.56...2864..213.5....354.....4...5379.563.425342......23.5.61.4..3.258..571.623. autosolve
375649128649821375182735496268417953791563842534298761823954617416372589957186234 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (19)
B1: 1,7
C2: 8,9
A3: 1,2
H2: 7,9
I3: 1,6
A4: 1,2
C5: 1,8
G5: 1,8
I6: 1,6
A7: 8,9
B8: 1,6
C8: 1,6
A9: 8,9
D7: 7,9
F7: 4,8
E8: 7,9
E9: 4,8
I8: 7,9
I9: 4,9

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
G1,I3: 1.. / G1 = 1  =>  0 pairs (*) / I3 = 1  =>  0 pairs (X)
E4,E6: 1.. / E4 = 1  =>  0 pairs (*) / E6 = 1  =>  0 pairs (X)
B8,C8: 1.. / B8 = 1  =>  0 pairs (*) / C8 = 1  =>  0 pairs (X)
B1,G1: 1.. / B1 = 1  =>  0 pairs (X) / G1 = 1  =>  0 pairs (_)
C5,G5: 1.. / C5 = 1  =>  0 pairs (*) / G5 = 1  =>  0 pairs (X)
A3,A4: 1.. / A3 = 1  =>  0 pairs (*) / A4 = 1  =>  0 pairs (X)
I3,I6: 1.. / I3 = 1  =>  0 pairs (X) / I6 = 1  =>  0 pairs (_)
A3,C3: 2.. / A3 = 2  =>  0 pairs (X) / C3 = 2  =>  0 pairs (_)
A4,C4: 2.. / A4 = 2  =>  0 pairs (*) / C4 = 2  =>  0 pairs (X)
A3,A4: 2.. / A3 = 2  =>  0 pairs (X) / A4 = 2  =>  0 pairs (_)
C3,C4: 2.. / C3 = 2  =>  0 pairs (*) / C4 = 2  =>  0 pairs (X)
E1,F1: 4.. / E1 = 4  => 16 pairs (_) / F1 = 4  =>  0 pairs (X)
F7,E9: 4.. / F7 = 4  => 16 pairs (_) / E9 = 4  =>  0 pairs (X)
I7,I9: 4.. / I7 = 4  =>  0 pairs (X) / I9 = 4  => 16 pairs (_)
F7,I7: 4.. / F7 = 4  => 16 pairs (_) / I7 = 4  =>  0 pairs (X)
E9,I9: 4.. / E9 = 4  =>  0 pairs (X) / I9 = 4  => 16 pairs (_)
E1,E9: 4.. / E1 = 4  => 16 pairs (_) / E9 = 4  =>  0 pairs (X)
F1,F7: 4.. / F1 = 4  =>  0 pairs (X) / F7 = 4  => 16 pairs (_)
H3,I3: 6.. / H3 = 6  =>  0 pairs (X) / I3 = 6  =>  0 pairs (_)
B4,C4: 6.. / B4 = 6  =>  0 pairs (*) / C4 = 6  =>  0 pairs (X)
H6,I6: 6.. / H6 = 6  =>  0 pairs (*) / I6 = 6  =>  0 pairs (X)
B8,C8: 6.. / B8 = 6  =>  0 pairs (X) / C8 = 6  =>  0 pairs (_)
B4,B8: 6.. / B4 = 6  =>  0 pairs (*) / B8 = 6  =>  0 pairs (X)
C4,C8: 6.. / C4 = 6  =>  0 pairs (X) / C8 = 6  =>  0 pairs (_)
H3,H6: 6.. / H3 = 6  =>  0 pairs (X) / H6 = 6  =>  0 pairs (_)
I3,I6: 6.. / I3 = 6  =>  0 pairs (*) / I6 = 6  =>  0 pairs (X)
B1,B3: 7.. / B1 = 7  =>  0 pairs (*) / B3 = 7  =>  0 pairs (X)
D7,E8: 7.. / D7 = 7  =>  0 pairs (X) / E8 = 7  => 19 pairs (_)
I7,I8: 7.. / I7 = 7  => 19 pairs (_) / I8 = 7  =>  0 pairs (X)
D2,H2: 7.. / D2 = 7  =>  0 pairs (X) / H2 = 7  => 22 pairs (_)
D7,I7: 7.. / D7 = 7  =>  0 pairs (X) / I7 = 7  => 19 pairs (_)
E8,I8: 7.. / E8 = 7  => 19 pairs (_) / I8 = 7  =>  0 pairs (X)
D2,D3: 8.. / D2 = 8  => 21 pairs (_) / D3 = 8  =>  0 pairs (X)
A7,A9: 8.. / A7 = 8  => 16 pairs (_) / A9 = 8  =>  0 pairs (X)
F7,E9: 8.. / F7 = 8  =>  0 pairs (X) / E9 = 8  => 16 pairs (_)
C2,D2: 8.. / C2 = 8  =>  0 pairs (X) / D2 = 8  => 21 pairs (_)
C5,G5: 8.. / C5 = 8  =>  0 pairs (X) / G5 = 8  =>  0 pairs (_)
A7,F7: 8.. / A7 = 8  => 16 pairs (_) / F7 = 8  =>  0 pairs (X)
A9,E9: 8.. / A9 = 8  =>  0 pairs (X) / E9 = 8  => 16 pairs (_)
B3,B4: 8.. / B3 = 8  =>  0 pairs (*) / B4 = 8  =>  0 pairs (X)
C2,C3: 9.. / C2 = 9  => 21 pairs (_) / C3 = 9  =>  0 pairs (X)
A7,A9: 9.. / A7 = 9  =>  0 pairs (X) / A9 = 9  => 16 pairs (_)
D7,E8: 9.. / D7 = 9  => 19 pairs (_) / E8 = 9  =>  0 pairs (X)
E8,I8: 9.. / E8 = 9  =>  0 pairs (X) / I8 = 9  => 19 pairs (_)
A9,I9: 9.. / A9 = 9  => 16 pairs (_) / I9 = 9  =>  0 pairs (X)
* DURATION: 0:01:24.593997  START: 09:17:47.204595  END: 09:19:11.798592 2017-05-04
* CP COUNT: (45)
* SOLUTION FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A3,A4,A7,A9,B1,B8,C2,C5,C8,D7,E8,E9,F7,G5,H2,I3,I6,I8,I9)
* 3.56...2864..213.5....354.....4...5379.563.425342......23.5.61.4..3.258..571.623.
* PAIR B1: 1,7 BLK 1
B3: 1,7,8                                # reduction candidate for 1,7
B3: 1,7 => CTR
* 3.56...2864..213.5....354...864...53791563.425342......23.5.61.4..3.258..571.623.
B3: 8 => SOLVED
* 375649128649821375182735496268417953791563842534298761823954617416372589957186234
* PAIR B1: 1,7 ROW 1
G1: 1,7,9                                # reduction candidate for 1,7
G1: 9 => CTR
* 3156..92864..2137527..3546118.4...5379.563.425342......23.5.61.4..3.258..571.623.
G1: 1,7                                  # 19 pairs
* PAIR C2: 8,9 BLK 1
C3: 8,9,1,2                              # reduction candidate for 8,9
C3: 8,9 => CTR
* 3.56...2864..213.52...354..1.24...53798563.425342......23.5.61.4..3.258..571.623.
C3: 1,2 => SOLVED
* 375649128649821375182735496268417953791563842534298761823954617416372589957186234
* PAIR C2: 8,9 ROW 2
D2: 8,9,7                                # reduction candidate for 8,9
D2: 7 => CTR
* 3.56...28648721395..98354...8.4...5379.563.425342......23.5.61.4..3.258..571.623.
D2: 8,9                                  # 22 pairs
* PAIR A3: 1,2 BLK 1
C3: 1,2,8,9                              # reduction candidate for 1,2
C3: 1,2 => SOLVED
* 375649128649821375182735496268417953791563842534298761823954617416372589957186234
C3: 8,9 => CTR
* 3.56...2864..213.52...354..1.24...53798563.425342......23.5.61.4..3.258..571.623.
* PAIR H2: 7,9 BLK 3
G1: 7,9,1                                # reduction candidate for 7,9
G1: 7,9 => CTR
* 3156...2864..213.527..354.118.4...5379.563.425342......23.5.61.4..3.258..571.623.
G1: 1 => SOLVED
* 375649128649821375182735496268417953791563842534298761823954617416372589957186234
H3: 7,9,6                                # reduction candidate for 7,9
H3: 7,9 => SOLVED
* 375649128649821375182735496268417953791563842534298761823954617416372589957186234
H3: 6 => CTR
* 3.56...2864..213.5....354611.24...53798563.425342......23.5.61.4..3.258..571.623.
* PAIR H2: 7,9 ROW 2
D2: 7,9,8                                # reduction candidate for 7,9
D2: 7,9 => CTR
* 3.56...28648.213.5..98354...8.4...5379.563.425342......23.5.61.4..3.258..571.623.
D2: 8                                    # 21 pairs
* PAIR H2: 7,9 COL H
H6: 7,9,6                                # reduction candidate for 7,9
H6: 7,9 => CTR
* 3.56...2864..213.5....354611.24...53798563.425342......23.5.61.4..3.258..571.623.
H6: 6 => SOLVED
* 375649128649821375182735496268417953791563842534298761823954617416372589957186234
* PAIR A4: 1,2 BLK 4
C4: 1,2,6,8                              # reduction candidate for 1,2
C4: 1,2 => CTR
* 3.56...2864..213.5....354...6.4...5379856314253421...6.23.5.61.4163.258..571.623.
C4: 6,8 => SOLVED
* 375649128649821375182735496268417953791563842534298761823954617416372589957186234
* PAIR C5: 1,8 BLK 4
B4: 1,8,6                                # reduction candidate for 1,8
B4: 1,8 => CTR
* 3.56...2864..213.5..2.354..2164...5379856314253421...6.23.5.61.4613.258..571.623.
B4: 6 => SOLVED
* 375649128649821375182735496268417953791563842534298761823954617416372589957186234
C4: 1,8,2,6                              # reduction candidate for 1,8
C4: 1,8 => SOLVED
* 375649128649821375182735496268417953791563842534298761823954617416372589957186234
C4: 2,6                                  # 20 pairs
* PAIR C5: 1,8 COL C
C3: 1,8,2,9                              # reduction candidate for 1,8
C3: 1,8 => CTR
* 3.56...286498213752...354..1.24...5379856314253421...6.23.5.61.4.63.258..571.623.
C3: 2,9                                  # 20 pairs
* PAIR G5: 1,8 BLK 6
G4: 1,8,7,9                              # reduction candidate for 1,8
G4: 1,8 => CTR
* 3.564..2864..213.5....354611.24..853798563.42534218..6823.5461.4..3.258.957186234
G4: 7,9                                  # 20 pairs
G6: 1,8,7,9                              # reduction candidate for 1,8
G6: 1,8 => CTR
* 3156...2864..213.527..3546118.4...5379.563.425342......23.5.61.4..3.258..571.623.
G6: 7,9                                  # 21 pairs
* PAIR B8: 1,6 COL B
B4: 1,6,8                                # reduction candidate for 1,6
B4: 1,6 => SOLVED
* 375649128649821375182735496268417953791563842534298761823954617416372589957186234
B4: 8 => CTR
* 3.56...2864..213.5....354...864...53791563.425342......23.5.61.4..3.258..571.623.
* PAIR C8: 1,6 COL C
C4: 1,6,2,8                              # reduction candidate for 1,6
C4: 1,6 => CTR
* 3.56...286498213751827354962..4...537985631425342......23.5.61.4..3.258..571.623.
C4: 2,8 => SOLVED
* 375649128649821375182735496268417953791563842534298761823954617416372589957186234
* PAIR D7: 7,9 ROW 7
I7: 7,9,4                                # reduction candidate for 7,9
I7: 4 => CTR
* 3.567492864..21375.7..3546118.4...5379.563.425342......2375.6144..392587.57146239
I7: 7,9                                  # 16 pairs
* PAIR D7: 7,9 COL D
D2: 7,9,8                                # reduction candidate for 7,9
D2: 7,9 => CTR
* 3.56...28648.213.5..98354...8.4...5379.563.425342......23.5.61.4..3.258..571.623.
D2: 8                                    # 21 pairs
D3: 7,9,8                                # reduction candidate for 7,9
D3: 7,9                                  # 21 pairs
* PAIR E8: 7,9 COL E
E1: 7,9,4                                # reduction candidate for 7,9
E1: 7,9 => CTR
* 3.567492864..21375.7..3546118.4...5379.563.425342.....9237586144..392587857146239
E1: 4                                    # 16 pairs
E4: 7,9,1,8                              # reduction candidate for 7,9
E4: 7,9 => CTR
* 3.564..2864..213.5....354611.24...53798563.4253421...6.23.5.61.4..3.258..57186234
E4: 1,8                                  # 22 pairs
E6: 7,9,1,8                              # reduction candidate for 7,9
E6: 7,9 => SOLVED
* 375649128649821375182735496268417953791563842534298761823954617416372589957186234
E6: 1,8                                  # 20 pairs
* PAIR I8: 7,9 BLK 9
I7: 7,9,4                                # reduction candidate for 7,9
I7: 4 => CTR
* 3.567492864..21375.7..3546118.4...5379.563.425342......2375.6144..392587.57146239
I7: 7,9                                  # 16 pairs
* PAIR I9: 4,9 BLK 9
I7: 4,9,7                                # reduction candidate for 4,9
I7: 4,9 => CTR
* 3.56...2864..21375.7..354...864...53791563.425342......2375.61.4..392587.571.623.
I7: 7                                    # 19 pairs
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-192-base-pr-000.dot
* REASONING
* DIS # B3: 1,7 => CTR => B3: 8
* PRF # B3: 8 => SOL
* DIS # G1: 9 => CTR => G1: 1,7
* DIS # C3: 8,9 => CTR => C3: 1,2
* PRF # C3: 1,2 => SOL
* DIS # D2: 7 => CTR => D2: 8,9
* PRF # C3: 1,2 => SOL
* DIS # C3: 8,9 => CTR => C3: 1,2
* DIS # G1: 7,9 => CTR => G1: 1
* PRF # G1: 1 => SOL
* PRF # H3: 7,9 => SOL
* DIS # H3: 6 => CTR => H3: 7,9
* DIS # D2: 7,9 => CTR => D2: 8
* DIS # H6: 7,9 => CTR => H6: 6
* PRF # H6: 6 => SOL
* DIS # C4: 1,2 => CTR => C4: 6,8
* PRF # C4: 6,8 => SOL
* DIS # B4: 1,8 => CTR => B4: 6
* PRF # B4: 6 => SOL
* PRF # C4: 1,8 => SOL
* DIS # C3: 1,8 => CTR => C3: 2,9
* DIS # G4: 1,8 => CTR => G4: 7,9
* DIS # G6: 1,8 => CTR => G6: 7,9
* PRF # B4: 1,6 => SOL
* DIS # B4: 8 => CTR => B4: 1,6
* DIS # C4: 1,6 => CTR => C4: 2,8
* PRF # C4: 2,8 => SOL
* DIS # I7: 4 => CTR => I7: 7,9
* DIS # D2: 7,9 => CTR => D2: 8
* DIS # E1: 7,9 => CTR => E1: 4
* DIS # E4: 7,9 => CTR => E4: 1,8
* PRF # E6: 7,9 => SOL
* DIS # I7: 4 => CTR => I7: 7,9
* DIS # I7: 4,9 => CTR => I7: 7
* CNT  34 HDP CHAINS /  49 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A3,A4,A7,A9,B1,B8,C2,C5,C8,D7,E8,E9,F7,G5,H2,I3,I6,I8,I9)
* 3.56...2864..213.5....354.....4...5379.563.425342......23.5.61.4..3.258..571.623.
* PAIR B1: 1,7 BLK 1
B3: 1,7,8                                # reduction candidate for 1,7
B3: 1,7 => CTR
* 3.56...2864..213.5....354...864...53791563.425342......23.5.61.4..3.258..571.623.
B3: 8 => SOLVED
* 375649128649821375182735496268417953791563842534298761823954617416372589957186234
* DURATION: 0:00:03.248439  START: 09:20:06.391527  END: 09:20:09.639966 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-192-base-pr-001.dot
* REASONING
* DIS # B3: 1,7 => CTR => B3: 8
* PRF B3: 8 => SOL
* STA B3: 8
* CNT   2 HDP CHAINS /   1 HYP OPENED

Header Info

Top 500 Minimum 17 192

solution: 375649128649821375182735496268417953791563842534298761823954617416372589957186234
info: 1844     FNBTWY   S8.f     29754

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

Solution

position: 375649128649821375182735496268417953791563842534298761823954617416372589957186234 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 # B3: 1,7 => CTR => B3: 8
* PRF # B3: 8 => SOL
* INC # G1: 1,7 => UNS
* DIS # G1: 9 => CTR => G1: 1,7
* DIS # C3: 8,9 => CTR => C3: 1,2
* PRF # C3: 1,2 => SOL
* INC # D2: 8,9 => UNS
* DIS # D2: 7 => CTR => D2: 8,9
* PRF # C3: 1,2 => SOL
* DIS # C3: 8,9 => CTR => C3: 1,2
* DIS # G1: 7,9 => CTR => G1: 1
* PRF # G1: 1 => SOL
* PRF # H3: 7,9 => SOL
* DIS # H3: 6 => CTR => H3: 7,9
* DIS # D2: 7,9 => CTR => D2: 8
* INC # D2: 8 => UNS
* DIS # H6: 7,9 => CTR => H6: 6
* PRF # H6: 6 => SOL
* DIS # C4: 1,2 => CTR => C4: 6,8
* PRF # C4: 6,8 => SOL
* DIS # B4: 1,8 => CTR => B4: 6
* PRF # B4: 6 => SOL
* PRF # C4: 1,8 => SOL
* INC # C4: 2,6 => UNS
* DIS # C3: 1,8 => CTR => C3: 2,9
* INC # C3: 2,9 => UNS
* DIS # G4: 1,8 => CTR => G4: 7,9
* INC # G4: 7,9 => UNS
* DIS # G6: 1,8 => CTR => G6: 7,9
* INC # G6: 7,9 => UNS
* PRF # B4: 1,6 => SOL
* DIS # B4: 8 => CTR => B4: 1,6
* DIS # C4: 1,6 => CTR => C4: 2,8
* PRF # C4: 2,8 => SOL
* INC # I7: 7,9 => UNS
* DIS # I7: 4 => CTR => I7: 7,9
* DIS # D2: 7,9 => CTR => D2: 8
* INC # D2: 8 => UNS
* INC # D3: 7,9 => UNS
* DIS # E1: 7,9 => CTR => E1: 4
* INC # E1: 4 => UNS
* DIS # E4: 7,9 => CTR => E4: 1,8
* INC # E4: 1,8 => UNS
* PRF # E6: 7,9 => SOL
* INC # E6: 1,8 => UNS
* INC # I7: 7,9 => UNS
* DIS # I7: 4 => CTR => I7: 7,9
* DIS # I7: 4,9 => CTR => I7: 7
* INC # I7: 7 => UNS
* CNT  49 HDP CHAINS /  49 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* DIS # B3: 1,7 => CTR => B3: 8
* PRF B3: 8 => SOL
* STA B3: 8
* CNT   2 HDP CHAINS /   1 HYP OPENED