Analysis of zz-sudoku-de-773218-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: ..6...4......7.5.88..96..1....2....3..17.68..5....4....5..31..66.9.2......2...1.. initial

Autosolve

position: ..61..439193472568845963.1....21...3.317.68..5..3.4..1.5.831..66195273843826491.. autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* DIS # B6: 6 => CTR => B6: 2,7
* DIS # G6: 2,7 => CTR => G6: 6,9
* DIS # B6: 6,7 => CTR => B6: 2
* DIS # G4: 9 => CTR => G4: 6,7
* DIS # C4: 4 => CTR => C4: 7,8
* PRF # H5: 5,9 => SOL
* PRF # H5: 2,5 => SOL
* DIS # A4: 4,7 => CTR => A4: 9
* DIS # C4: 4,7 => CTR => C4: 8
* PRF # C4: 8 => SOL
* DIS # G6: 2,9 => CTR => G6: 6,7
* DIS # H5: 2,9 => CTR => H5: 4,5
* PRF # H4: 4,9 => SOL
* CNT  13 HDP CHAINS /  25 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 # B6: 6 => CTR => B6: 2,7
* DIS B6: 2,7 # C4: 4 => CTR => C4: 7,8
* PRF B6: 2,7 + C4: 7,8 # H5: 2,5 => SOL
* STA B6: 2,7 + C4: 7,8 + H5: 2,5
* CNT   3 HDP CHAINS /   5 HYP OPENED

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

Details

Positions

..6...4......7.5.88..96..1....2....3..17.68..5....4....5..31..66.9.2......2...1.. initial
..61..439193472568845963.1....21...3.317.68..5..3.4..1.5.831..66195273843826491.. autosolve
276158439193472568845963217968215743431796852527384691754831926619527384382649175 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (18)
A1: 2,7
B1: 2,7
E1: 5,8
F1: 5,8
G3: 2,7
I3: 2,7
B4: 6,7
C6: 7,8
F4: 5,8
E5: 5,9
E6: 8,9
I5: 2,5
A7: 4,7
C7: 4,7
G7: 2,9
H7: 2,9
H9: 5,7
I9: 5,7

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
A1,B1: 2.. / A1 = 2  => 19 pairs (_) / B1 = 2  =>  0 pairs (X)
G3,I3: 2.. / G3 = 2  =>  0 pairs (*) / I3 = 2  =>  0 pairs (X)
A5,B6: 2.. / A5 = 2  =>  0 pairs (X) / B6 = 2  => 19 pairs (_)
G7,H7: 2.. / G7 = 2  =>  0 pairs (X) / H7 = 2  => 22 pairs (_)
A1,A5: 2.. / A1 = 2  => 19 pairs (_) / A5 = 2  =>  0 pairs (X)
B1,B6: 2.. / B1 = 2  =>  0 pairs (X) / B6 = 2  => 19 pairs (_)
I3,I5: 2.. / I3 = 2  =>  0 pairs (X) / I5 = 2  =>  0 pairs (_)
H4,H5: 4.. / H4 = 4  =>  0 pairs (*) / H5 = 4  =>  0 pairs (X)
A7,C7: 4.. / A7 = 4  =>  0 pairs (X) / C7 = 4  => 19 pairs (_)
A5,H5: 4.. / A5 = 4  =>  0 pairs (*) / H5 = 4  =>  0 pairs (X)
C4,C7: 4.. / C4 = 4  =>  0 pairs (X) / C7 = 4  => 19 pairs (_)
E1,F1: 5.. / E1 = 5  =>  0 pairs (*) / F1 = 5  =>  0 pairs (X)
F4,E5: 5.. / F4 = 5  =>  0 pairs (*) / E5 = 5  =>  0 pairs (X)
H9,I9: 5.. / H9 = 5  =>  0 pairs (X) / I9 = 5  =>  0 pairs (_)
F4,H4: 5.. / F4 = 5  =>  0 pairs (*) / H4 = 5  =>  0 pairs (X)
E1,E5: 5.. / E1 = 5  =>  0 pairs (*) / E5 = 5  =>  0 pairs (X)
F1,F4: 5.. / F1 = 5  =>  0 pairs (X) / F4 = 5  =>  0 pairs (_)
I5,I9: 5.. / I5 = 5  =>  0 pairs (X) / I9 = 5  =>  0 pairs (_)
B4,B6: 6.. / B4 = 6  => 19 pairs (_) / B6 = 6  =>  0 pairs (X)
G4,G6: 6.. / G4 = 6  =>  0 pairs (X) / G6 = 6  => 19 pairs (_)
B4,G4: 6.. / B4 = 6  => 19 pairs (_) / G4 = 6  =>  0 pairs (X)
B6,G6: 6.. / B6 = 6  =>  0 pairs (X) / G6 = 6  => 19 pairs (_)
A1,B1: 7.. / A1 = 7  =>  0 pairs (X) / B1 = 7  => 19 pairs (_)
G3,I3: 7.. / G3 = 7  =>  0 pairs (X) / I3 = 7  =>  0 pairs (_)
A7,C7: 7.. / A7 = 7  => 19 pairs (_) / C7 = 7  =>  0 pairs (X)
H9,I9: 7.. / H9 = 7  =>  0 pairs (*) / I9 = 7  =>  0 pairs (X)
I3,I9: 7.. / I3 = 7  =>  0 pairs (*) / I9 = 7  =>  0 pairs (X)
E1,F1: 8.. / E1 = 8  =>  0 pairs (X) / F1 = 8  =>  0 pairs (_)
C4,C6: 8.. / C4 = 8  =>  0 pairs (*) / C6 = 8  =>  0 pairs (X)
F4,E6: 8.. / F4 = 8  =>  0 pairs (X) / E6 = 8  =>  0 pairs (_)
C4,F4: 8.. / C4 = 8  =>  0 pairs (*) / F4 = 8  =>  0 pairs (X)
C6,E6: 8.. / C6 = 8  =>  0 pairs (X) / E6 = 8  =>  0 pairs (_)
E1,E6: 8.. / E1 = 8  =>  0 pairs (X) / E6 = 8  =>  0 pairs (_)
F1,F4: 8.. / F1 = 8  =>  0 pairs (*) / F4 = 8  =>  0 pairs (X)
A4,A5: 9.. / A4 = 9  => 22 pairs (_) / A5 = 9  =>  0 pairs (X)
E5,E6: 9.. / E5 = 9  =>  0 pairs (*) / E6 = 9  =>  0 pairs (X)
G7,H7: 9.. / G7 = 9  => 22 pairs (_) / H7 = 9  =>  0 pairs (X)
* DURATION: 0:01:00.226734  START: 08:45:01.468630  END: 08:46:01.695364 2017-05-01
* CP COUNT: (37)
* SOLUTION FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A1,A7,B1,B4,C6,C7,E1,E5,E6,F1,F4,G3,G7,H7,H9,I3,I5,I9)
* ..61..439193472568845963.1....21...3.317.68..5..3.4..1.5.831..66195273843826491..
* PAIR B1: 2,7 COL B
B6: 2,7,6                                # reduction candidate for 2,7
B6: 6 => CTR
* .261..439193472568845963.1..7.21.6.32317.6845568394..1.5.831..66195273843826491..
B6: 2,7                                  # 19 pairs
* PAIR G3: 2,7 COL G
G6: 2,7,6,9                              # reduction candidate for 2,7
G6: 2,7 => CTR
* .261..439193472568845963.1..7.21.6.32317.6845568394..1.5.8319266195273843826491..
G6: 6,9                                  # 19 pairs
* PAIR B4: 6,7 BLK 4
B6: 6,7,2                                # reduction candidate for 6,7
B6: 6,7 => CTR
* 7261584391934725688459637129..21...32317.68455..3.4..1.5.831..6619527384382649157
B6: 2                                    # 19 pairs
* PAIR B4: 6,7 ROW 4
G4: 6,7,9                                # reduction candidate for 6,7
G4: 9 => CTR
* ..61..439193472568845963.1..6.21.9.393175684252.394671.5.831..66195273843826491..
G4: 6,7                                  # 21 pairs
* PAIR C6: 7,8 BLK 4
C4: 7,8,4                                # reduction candidate for 7,8
C4: 4 => CTR
* ..61..439193472568845963.1...4218.53.31756842528394671.5.831..66195273843826491..
C4: 7,8                                  # 19 pairs
* PAIR E5: 5,9 ROW 5
H5: 5,9,2,4                              # reduction candidate for 5,9
H5: 5,9 => SOLVED
* 276158439193472568845963217968215743431796852527384691754831926619527384382649175
H5: 2,4                                  # 19 pairs
* PAIR I5: 2,5 BLK 6
H5: 2,5,4,9                              # reduction candidate for 2,5
H5: 2,5 => SOLVED
* 276158439193472568845963217968215743431796852527384691754831926619527384382649175
H5: 4,9                                  # 19 pairs
* PAIR A7: 4,7 COL A
A4: 4,7,9                                # reduction candidate for 4,7
A4: 4,7 => CTR
* ..61..439193472568845963.1....21...393175684252.394671.5.831.266195273843826491..
A4: 9                                    # 22 pairs
* PAIR C7: 4,7 COL C
C4: 4,7,8                                # reduction candidate for 4,7
C4: 4,7 => CTR
* ..61..439193472568845963.1....218.53.31756842528394671.5.831..66195273843826491..
C4: 8 => SOLVED
* 276158439193472568845963217968215743431796852527384691754831926619527384382649175
* PAIR G7: 2,9 COL G
G6: 2,9,6,7                              # reduction candidate for 2,9
G6: 2,9 => CTR
* .261..439193472568845963712.7.21.6.32317.6845568394..1.5.831..66195273843826491..
G6: 6,7                                  # 19 pairs
* PAIR H7: 2,9 COL H
H5: 2,9,4,5                              # reduction candidate for 2,9
H5: 2,9 => CTR
* 2761584391934725688459637129..21..434317.68.552.3.46.1754831..6619527384382649157
H5: 4,5                                  # 19 pairs
H6: 2,9,7                                # reduction candidate for 2,9
H6: 2,9                                  # 20 pairs
* PAIR H9: 5,7 COL H
H4: 5,7,4,9                              # reduction candidate for 5,7
H4: 4,9 => SOLVED
* 276158439193472568845963217968215743431796852527384691754831926619527384382649175
H4: 5,7                                  # 21 pairs
* INCONCLUSIVE
* SAVE PR GRAPH zz-sudoku-de-773218-base-pr-000.dot
* REASONING
* DIS # B6: 6 => CTR => B6: 2,7
* DIS # G6: 2,7 => CTR => G6: 6,9
* DIS # B6: 6,7 => CTR => B6: 2
* DIS # G4: 9 => CTR => G4: 6,7
* DIS # C4: 4 => CTR => C4: 7,8
* PRF # H5: 5,9 => SOL
* PRF # H5: 2,5 => SOL
* DIS # A4: 4,7 => CTR => A4: 9
* DIS # C4: 4,7 => CTR => C4: 8
* PRF # C4: 8 => SOL
* DIS # G6: 2,9 => CTR => G6: 6,7
* DIS # H5: 2,9 => CTR => H5: 4,5
* PRF # H4: 4,9 => SOL
* CNT  13 HDP CHAINS /  25 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A1,A7,B1,B4,C6,C7,E1,E5,E6,F1,F4,G3,G7,H7,H9,I3,I5,I9)
* ..61..439193472568845963.1....21...3.317.68..5..3.4..1.5.831..66195273843826491..
* PAIR B1: 2,7 COL B
B6: 2,7,6                                # reduction candidate for 2,7
B6: 6 => CTR
* .261..439193472568845963.1..7.21.6.32317.6845568394..1.5.831..66195273843826491..
* PAIR RESTART
* PAIR C6: 7,8 BLK 4
C4: 7,8,4                                # reduction candidate for 7,8
C4: 4 => CTR
* ..61..439193472568845963.1..64218.53.31756842528394671.5.831..66195273843826491..
* PAIR I5: 2,5 BLK 6
H5: 2,5,4                                # reduction candidate for 2,5
H5: 2,5 => SOLVED
* 276158439193472568845963217968215743431796852527384691754831926619527384382649175
* DURATION: 0:00:06.209135  START: 08:46:26.067980  END: 08:46:32.277115 2017-05-01
* SOLUTION FOUND
* SAVE PR GRAPH zz-sudoku-de-773218-base-pr-001.dot
* REASONING
* DIS # B6: 6 => CTR => B6: 2,7
* DIS B6: 2,7 # C4: 4 => CTR => C4: 7,8
* PRF B6: 2,7 + C4: 7,8 # H5: 2,5 => SOL
* STA B6: 2,7 + C4: 7,8 + H5: 2,5
* CNT   3 HDP CHAINS /   5 HYP OPENED

Header Info

http://www.sudokus.de/773218.html
sehr schwierig

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

* PAIR REDUCTION ..
* ROUND 1: ..61..439193472568845963.1....21...3.317.68..5..3.4..1.5.831..66195273843826491..
A1: 2,7
B1: 2,7
B6: 2,6,7                                # reduction candidate for 2,7
B6: 6 => CTR
* .261..439193472568845963.1..7.21.6.32317.6845568394..1.5.831..66195273843826491..
E1: 5,8
F1: 5,8
G3: 2,7
I3: 2,7
C6: 7,8
C4: 4,7,8                                # reduction candidate for 7,8
C4: 4 => CTR
* ..61..439193472568845963.1..64218.53.31756842528394671.5.831..66195273843826491..
F4: 5,8
E5: 5,9
E6: 8,9
I5: 2,5
H5: 2,4,5                                # reduction candidate for 2,5
H5: 2,5 => SOLVED
* 276158439193472568845963217968215743431796852527384691754831926619527384382649175
* SOLVED!
--------------------------------------------------

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

optional pair quad 2,9
G6: 2,6,7,9
H6: 2,7,9
G7: 2,9
H7: 2,9

pair quad 4,7
A4: 4,7,9
C4: 4,7,8
A7: 4,7
C7: 4,7

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

Solution

position: 276158439193472568845963217968215743431796852527384691754831926619527384382649175 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 # B6: 2,7 => UNS
* DIS # B6: 6 => CTR => B6: 2,7
* DIS # G6: 2,7 => CTR => G6: 6,9
* INC # G6: 6,9 => UNS
* DIS # B6: 6,7 => CTR => B6: 2
* INC # B6: 2 => UNS
* INC # G4: 6,7 => UNS
* DIS # G4: 9 => CTR => G4: 6,7
* INC # C4: 7,8 => UNS
* DIS # C4: 4 => CTR => C4: 7,8
* PRF # H5: 5,9 => SOL
* INC # H5: 2,4 => UNS
* PRF # H5: 2,5 => SOL
* INC # H5: 4,9 => UNS
* DIS # A4: 4,7 => CTR => A4: 9
* INC # A4: 9 => UNS
* DIS # C4: 4,7 => CTR => C4: 8
* PRF # C4: 8 => SOL
* DIS # G6: 2,9 => CTR => G6: 6,7
* INC # G6: 6,7 => UNS
* DIS # H5: 2,9 => CTR => H5: 4,5
* INC # H5: 4,5 => UNS
* INC # H6: 2,9 => UNS
* INC # H4: 5,7 => UNS
* PRF # H4: 4,9 => SOL
* CNT  25 HDP CHAINS /  25 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* INC # B6: 2,7 => UNS
* DIS # B6: 6 => CTR => B6: 2,7
* INC B6: 2,7 # C4: 7,8 => UNS
* DIS B6: 2,7 # C4: 4 => CTR => C4: 7,8
* PRF B6: 2,7 + C4: 7,8 # H5: 2,5 => SOL
* STA B6: 2,7 + C4: 7,8 + H5: 2,5
* CNT   5 HDP CHAINS /   5 HYP OPENED