Analysis of zz-sudoku-de-759127-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: 8.2..5.3.....78..41...9.8....5....7...15.62...2....5....4.8...76..95.....1.3..4.6 initial

Autosolve

position: 8.2.6573.....78..41...938.5..58.2.7.7.15.62...2.7.95..2.4681..76..954..2.1.3274.6 autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* DIS # B3: 4 => CTR => B3: 6,7
* PRF # H2: 6,9 => SOL
* DIS # H2: 1,9 => CTR => H2: 2,6
* DIS # H2: 1,9 => CTR => H2: 2,6
* DIS # A4: 9 => CTR => A4: 3,4
* DIS # E6: 3,4 => CTR => E6: 1
* DIS # E6: 3,4 => CTR => E6: 1
* DIS # B7: 5,9 => CTR => B7: 3
* DIS # H9: 5,9 => CTR => H9: 8
* DIS # A2: 3 => CTR => A2: 5,9
* DIS # H9: 5 => CTR => H9: 8,9
* DIS # B7: 5 => CTR => B7: 3,9
* DIS # H9: 5,9 => CTR => H9: 8
* DIS # B7: 5,9 => CTR => B7: 3
* CNT  14 HDP CHAINS /  32 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: 4 => CTR => B3: 6,7
* DIS B3: 6,7 # A4: 9 => CTR => A4: 3,4
* DIS B3: 6,7 + A4: 3,4 # E6: 3,4 => CTR => E6: 1
* PRF B3: 6,7 + A4: 3,4 + E6: 1 # C8: 7,8 => SOL
* STA B3: 6,7 + A4: 3,4 + E6: 1 + C8: 7,8
* CNT   4 HDP CHAINS /   6 HYP OPENED

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

Details

Positions

8.2..5.3.....78..41...9.8....5....7...15.62...2....5....4.8...76..95.....1.3..4.6 initial
8.2.6573.....78..41...938.5..58.2.7.7.15.62...2.7.95..2.4681..76..954..2.1.3274.6 autosolve
842165739953278164167493825495832671781546293326719548234681957678954312519327486 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (16)
B1: 4,9
C3: 6,7
D1: 1,4
D2: 1,2
D3: 2,4
I1: 1,9
H3: 2,6
A6: 3,4
E5: 3,4
H5: 4,9
A9: 5,9
C9: 8,9
G7: 3,9
H7: 5,9
G8: 1,3
H8: 1,8

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
D1,D2: 1.. / D1 = 1  => 18 pairs (_) / D2 = 1  =>  0 pairs (X)
E4,E6: 1.. / E4 = 1  =>  0 pairs (X) / E6 = 1  => 19 pairs (_)
G8,H8: 1.. / G8 = 1  =>  0 pairs (X) / H8 = 1  => 19 pairs (_)
D1,I1: 1.. / D1 = 1  => 18 pairs (_) / I1 = 1  =>  0 pairs (X)
D2,D3: 2.. / D2 = 2  => 18 pairs (_) / D3 = 2  =>  0 pairs (X)
H2,H3: 2.. / H2 = 2  =>  0 pairs (X) / H3 = 2  => 18 pairs (_)
D2,H2: 2.. / D2 = 2  => 18 pairs (_) / H2 = 2  =>  0 pairs (X)
D3,H3: 2.. / D3 = 2  =>  0 pairs (X) / H3 = 2  => 18 pairs (_)
G7,G8: 3.. / G7 = 3  =>  0 pairs (X) / G8 = 3  => 19 pairs (_)
B7,G7: 3.. / B7 = 3  => 19 pairs (_) / G7 = 3  =>  0 pairs (X)
B1,B3: 4.. / B1 = 4  => 18 pairs (_) / B3 = 4  =>  0 pairs (X)
D1,D3: 4.. / D1 = 4  =>  0 pairs (X) / D3 = 4  => 18 pairs (_)
A4,A6: 4.. / A4 = 4  => 28 pairs (_) / A6 = 4  =>  0 pairs (X)
H5,H6: 4.. / H5 = 4  => 19 pairs (_) / H6 = 4  =>  0 pairs (*)
B1,D1: 4.. / B1 = 4  => 18 pairs (_) / D1 = 4  =>  0 pairs (X)
B3,D3: 4.. / B3 = 4  =>  0 pairs (X) / D3 = 4  => 18 pairs (_)
A4,E4: 4.. / A4 = 4  => 28 pairs (_) / E4 = 4  =>  0 pairs (X)
E5,H5: 4.. / E5 = 4  =>  0 pairs (*) / H5 = 4  =>  0 pairs (X)
A2,B2: 5.. / A2 = 5  =>  0 pairs (X) / B2 = 5  => 17 pairs (_)
B7,A9: 5.. / B7 = 5  =>  0 pairs (X) / A9 = 5  => 17 pairs (_)
H7,H9: 5.. / H7 = 5  => 17 pairs (_) / H9 = 5  =>  0 pairs (X)
B7,H7: 5.. / B7 = 5  =>  0 pairs (X) / H7 = 5  => 17 pairs (_)
A9,H9: 5.. / A9 = 5  => 17 pairs (_) / H9 = 5  =>  0 pairs (X)
A2,A9: 5.. / A2 = 5  =>  0 pairs (X) / A9 = 5  => 17 pairs (_)
B2,B7: 5.. / B2 = 5  => 17 pairs (_) / B7 = 5  =>  0 pairs (X)
B4,C6: 6.. / B4 = 6  =>  0 pairs (X) / C6 = 6  => 24 pairs (_)
G4,H6: 6.. / G4 = 6  => 24 pairs (_) / H6 = 6  =>  0 pairs (X)
B4,G4: 6.. / B4 = 6  =>  0 pairs (X) / G4 = 6  => 24 pairs (_)
C6,H6: 6.. / C6 = 6  => 24 pairs (_) / H6 = 6  =>  0 pairs (X)
G2,G4: 6.. / G2 = 6  =>  0 pairs (X) / G4 = 6  => 24 pairs (_)
B3,C3: 7.. / B3 = 7  =>  0 pairs (X) / C3 = 7  => 21 pairs (_)
B8,C8: 7.. / B8 = 7  => 21 pairs (_) / C8 = 7  =>  0 pairs (X)
B3,B8: 7.. / B3 = 7  =>  0 pairs (X) / B8 = 7  => 21 pairs (_)
C3,C8: 7.. / C3 = 7  => 21 pairs (_) / C8 = 7  =>  0 pairs (X)
B5,C6: 8.. / B5 = 8  => 21 pairs (_) / C6 = 8  =>  0 pairs (X)
I5,I6: 8.. / I5 = 8  =>  0 pairs (X) / I6 = 8  => 21 pairs (_)
H8,H9: 8.. / H8 = 8  =>  0 pairs (X) / H9 = 8  => 19 pairs (_)
B5,I5: 8.. / B5 = 8  => 21 pairs (_) / I5 = 8  =>  0 pairs (X)
C6,I6: 8.. / C6 = 8  =>  0 pairs (X) / I6 = 8  => 21 pairs (_)
C9,H9: 8.. / C9 = 8  =>  0 pairs (X) / H9 = 8  => 19 pairs (_)
B5,B8: 8.. / B5 = 8  => 21 pairs (_) / B8 = 8  =>  0 pairs (X)
B1,I1: 9.. / B1 = 9  =>  0 pairs (X) / I1 = 9  => 18 pairs (_)
C2,C9: 9.. / C2 = 9  =>  0 pairs (X) / C9 = 9  => 19 pairs (_)
* DURATION: 0:01:08.225413  START: 08:33:28.553240  END: 08:34:36.778653 2017-05-01
* CP COUNT: (43)
* SOLUTION FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A6,A9,B1,C3,C9,D1,D2,D3,E5,G7,G8,H3,H5,H7,H8,I1)
* 8.2.6573.....78..41...938.5..58.2.7.7.15.62...2.7.95..2.4681..76..954..2.1.3274.6
* PAIR C3: 6,7 BLK 1
B3: 6,7,4                                # reduction candidate for 6,7
B3: 4 => CTR
* 892465731.631789.4147293865..58.267.7.15.62...267.95.82.4681..767.954..2.1.3274.6
B3: 6,7                                  # 18 pairs
* PAIR D2: 1,2 ROW 2
H2: 1,2,6,9                              # reduction candidate for 1,2
H2: 6,9 => SOLVED
* 842165739953278164167493825495832671781546293326719548234681957678954312519327486
H2: 1,2                                  # 18 pairs
* PAIR I1: 1,9 BLK 3
G2: 1,9,6                                # reduction candidate for 1,9
G2: 1,9                                  # 24 pairs
H2: 1,9,2,6                              # reduction candidate for 1,9
H2: 1,9 => CTR
* 842165739...2786141.6493825.658.2.7.7.15.624..2.7.956.2.4681..76.7954182.183274.6
H2: 2,6                                  # 24 pairs
* PAIR I1: 1,9 COL I
I4: 1,9,3                                # reduction candidate for 1,9
I4: 3                                    # 21 pairs
I4: 1,9                                  # 19 pairs
* PAIR H3: 2,6 BLK 3
H2: 2,6,1,9                              # reduction candidate for 2,6
H2: 1,9 => CTR
* 842165739...2786141.6493825.658.2.7.7.15.624..2.7.956.2.4681..76.7954182.183274.6
H2: 2,6                                  # 24 pairs
* PAIR A6: 3,4 BLK 4
A4: 3,4,9                                # reduction candidate for 3,4
A4: 9 => CTR
* 8924657313561789241...938.59.5842.7.7.153624942.7195682.4681..76..954..251.3274.6
A4: 3,4                                  # 27 pairs
* PAIR A6: 3,4 ROW 6
E6: 3,4,1                                # reduction candidate for 3,4
E6: 3,4 => CTR
* 842165739...278..41..4938254.58129737915362483287495612.468139768.954..2.1.3274.6
E6: 1                                    # 19 pairs
* PAIR E5: 3,4 BLK 5
E4: 3,4,1                                # reduction candidate for 3,4
E4: 3,4                                  # 19 pairs
E6: 3,4,1                                # reduction candidate for 3,4
E6: 3,4 => CTR
* 842165739...278..41..4938254.58129737915362483287495612.468139768.954..2.1.3274.6
E6: 1                                    # 19 pairs
* PAIR A9: 5,9 BLK 7
B7: 5,9,3                                # reduction candidate for 5,9
B7: 5,9 => CTR
* 8.2.6573...9.786.41...93825.658.297.7.15.62...2.7.95..2.46813.76..954182.183274.6
B7: 3                                    # 19 pairs
* PAIR A9: 5,9 ROW 9
H9: 5,9,8                                # reduction candidate for 5,9
H9: 5,9 => CTR
* 842165739..92786141..493825.658.29717815.6243.2.7.95.82.4681..76..954182.183274.6
H9: 8                                    # 19 pairs
* PAIR A9: 5,9 COL A
A2: 5,9,3                                # reduction candidate for 5,9
A2: 3 => CTR
* 8924657313561789241...938.59.5842.7.7.153624942.7195682.4681.576..954..251.3274.6
A2: 5,9                                  # 27 pairs
* PAIR C9: 8,9 ROW 9
H9: 8,9,5                                # reduction candidate for 8,9
H9: 5 => CTR
* 8421657395392786141..493825..58.2.7.7815.62...2.7.95.82546813976..954182918327456
H9: 8,9                                  # 17 pairs
* PAIR G7: 3,9 ROW 7
B7: 3,9,5                                # reduction candidate for 3,9
B7: 5 => CTR
* 8.2.6573.5.9.786.41...93825.658.297.7.15.62...2.7.95..2546813976..954182918327456
B7: 3,9                                  # 17 pairs
* PAIR H7: 5,9 BLK 9
H9: 5,9,8                                # reduction candidate for 5,9
H9: 5,9 => CTR
* 842165739..92786141..493825.658.29717815.6243.2.7.95.82.4681..76..954182.183274.6
H9: 8                                    # 19 pairs
* PAIR H7: 5,9 ROW 7
B7: 5,9,3                                # reduction candidate for 5,9
B7: 5,9 => CTR
* 8.2.6573...9.786.41...93825.658.297.7.15.62...2.7.95..2.46813.76..954182.183274.6
B7: 3                                    # 19 pairs
* INCONCLUSIVE
* SAVE PR GRAPH zz-sudoku-de-759127-base-pr-000.dot
* REASONING
* DIS # B3: 4 => CTR => B3: 6,7
* PRF # H2: 6,9 => SOL
* DIS # H2: 1,9 => CTR => H2: 2,6
* DIS # H2: 1,9 => CTR => H2: 2,6
* DIS # A4: 9 => CTR => A4: 3,4
* DIS # E6: 3,4 => CTR => E6: 1
* DIS # E6: 3,4 => CTR => E6: 1
* DIS # B7: 5,9 => CTR => B7: 3
* DIS # H9: 5,9 => CTR => H9: 8
* DIS # A2: 3 => CTR => A2: 5,9
* DIS # H9: 5 => CTR => H9: 8,9
* DIS # B7: 5 => CTR => B7: 3,9
* DIS # H9: 5,9 => CTR => H9: 8
* DIS # B7: 5,9 => CTR => B7: 3
* CNT  14 HDP CHAINS /  32 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A6,A9,B1,C3,C9,D1,D2,D3,E5,G7,G8,H3,H5,H7,H8,I1)
* 8.2.6573.....78..41...938.5..58.2.7.7.15.62...2.7.95..2.4681..76..954..2.1.3274.6
* PAIR C3: 6,7 BLK 1
B3: 6,7,4                                # reduction candidate for 6,7
B3: 4 => CTR
* 892465731.631789.4147293865..58.267.7.15.62...267.95.82.4681..767.954..2.1.3274.6
* PAIR A6: 3,4 BLK 4
A4: 3,4,9                                # reduction candidate for 3,4
A4: 9 => CTR
* 842165739...278..41..4938259.584267.7.15.62...2.7.95..2.4681..76..954..2.1.3274.6
* PAIR A6: 3,4 ROW 6
E6: 3,4,1                                # reduction candidate for 3,4
E6: 3,4 => CTR
* 842165739...278..41..493825..5812.737.15362483287495612.4681.976879543.2.1.3274.6
* PAIR RESTART

* LEVEL 0 PASS 1 ROUND 2 (AUTO SOLVE) (A2,A4,A6,A9,B2,B3,B4,B5,B7,B8,C2,C3,C6,C9,E4,E5,G2,G4,G7,G8,H2,H5,H6,H7,H8,H9,I5,I6)
* 842165739...278..41..493825..58.2.717.15.62...2.7195..2.4681..76..954..2.1.3274.6
* PAIR B8: 7,8 BLK 7
C8: 7,8,3                                # reduction candidate for 7,8
C8: 7,8 => SOLVED
* 842165739953278164167493825495832671781546293326719548234681957678954312519327486
* DURATION: 0:00:09.537985  START: 08:35:04.903470  END: 08:35:14.441455 2017-05-01
* SOLUTION FOUND
* SAVE PR GRAPH zz-sudoku-de-759127-base-pr-001.dot
* REASONING
* DIS # B3: 4 => CTR => B3: 6,7
* DIS B3: 6,7 # A4: 9 => CTR => A4: 3,4
* DIS B3: 6,7 + A4: 3,4 # E6: 3,4 => CTR => E6: 1
* PRF B3: 6,7 + A4: 3,4 + E6: 1 # C8: 7,8 => SOL
* STA B3: 6,7 + A4: 3,4 + E6: 1 + C8: 7,8
* CNT   4 HDP CHAINS /   6 HYP OPENED

Header Info

http://www.sudokus.de/759127.html
sehr schwierig

--------------------------------------------------
level: medium

* PAIR REDUCTION ..
* ROUND 1: 8.2.6573.....78..41...938.5..58.2.7.7.15.62...2.7.95..2.4681..76..954..2.1.3274.6
B1: 4,9
C3: 6,7
B3: 4,6,7                                # reduction candidate for 6,7
B3: 4 => CTR
* 892465731.631789.4147293865..58.267.7.15.62...267.95.82.4681..767.954..2.1.3274.6
A6: 3,4
A4: 3,4,9                                # reduction candidate for 3,4
A4: 9 => CTR
* 842165739...278..41..4938259.584267.7.15.62...2.7.95..2.4681..76..954..2.1.3274.6
E6: 1,3,4                                # reduction candidate for 3,4
E6: 3,4 => CTR
* 842165739...278..41..493825..5812.737.15362483287495612.4681.976879543.2.1.3274.6
E5: 3,4
H5: 4,9
A9: 5,9
C9: 8,9
G7: 3,9
H7: 5,9
G8: 1,3
H8: 1,8
* ROUND 2: 842165739...278..41..493825..58.2.717.15.62...2.7195..2.4681..76..954..2.1.3274.6
A2: 5,9
B2: 3,5
C2: 3,9
B3: 6,7
C3: 6,7
G2: 1,6
H2: 1,6
A4: 3,4
B4: 6,9
B5: 8,9
A6: 3,4
C6: 6,8
E4: 3,4
E5: 3,4
G4: 6,9
H5: 4,9
I5: 3,8
H6: 4,6
I6: 3,8
B7: 3,5
B8: 7,8
C8: 3,7,8                                # reduction candidate for 7,8
C8: 7,8 => SOLVED
* 842165739953278164167493825495832671781546293326719548234681957678954312519327486
* SOLVED!
--------------------------------------------------

|:step:| 00
--------------------------------------------------

* FORCE VALUE:: E4 = 3
E4 = 3                # set value
E5: 4                 # naked single
E6: 1..               # hidden single
A4: 4..               # hidden single

|:step:| 01
--------------------------------------------------

Solution

position: 842165739953278164167493825495832671781546293326719548234681957678954312519327486 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 # B3: 6,7 => UNS
* DIS # B3: 4 => CTR => B3: 6,7
* INC # H2: 1,2 => UNS
* PRF # H2: 6,9 => SOL
* INC # G2: 1,9 => UNS
* DIS # H2: 1,9 => CTR => H2: 2,6
* INC # H2: 2,6 => UNS
* INC # I4: 1,9 => UNS
* INC # I4: 3 => UNS
* INC # H2: 2,6 => UNS
* DIS # H2: 1,9 => CTR => H2: 2,6
* INC # A4: 3,4 => UNS
* DIS # A4: 9 => CTR => A4: 3,4
* DIS # E6: 3,4 => CTR => E6: 1
* INC # E6: 1 => UNS
* INC # E4: 3,4 => UNS
* DIS # E6: 3,4 => CTR => E6: 1
* INC # E6: 1 => UNS
* DIS # B7: 5,9 => CTR => B7: 3
* INC # B7: 3 => UNS
* DIS # H9: 5,9 => CTR => H9: 8
* INC # H9: 8 => UNS
* INC # A2: 5,9 => UNS
* DIS # A2: 3 => CTR => A2: 5,9
* INC # H9: 8,9 => UNS
* DIS # H9: 5 => CTR => H9: 8,9
* INC # B7: 3,9 => UNS
* DIS # B7: 5 => CTR => B7: 3,9
* DIS # H9: 5,9 => CTR => H9: 8
* INC # H9: 8 => UNS
* DIS # B7: 5,9 => CTR => B7: 3
* INC # B7: 3 => UNS
* CNT  32 HDP CHAINS /  32 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* INC # B3: 6,7 => UNS
* DIS # B3: 4 => CTR => B3: 6,7
* INC B3: 6,7 # A4: 3,4 => UNS
* DIS B3: 6,7 # A4: 9 => CTR => A4: 3,4
* DIS B3: 6,7 + A4: 3,4 # E6: 3,4 => CTR => E6: 1
* PRF B3: 6,7 + A4: 3,4 + E6: 1 # C8: 7,8 => SOL
* STA B3: 6,7 + A4: 3,4 + E6: 1 + C8: 7,8
* CNT   6 HDP CHAINS /   6 HYP OPENED