Analysis of zz-sudoku-de-703274-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: .....7..98.1..34...4.....31..8.7...3...6.2...6...1.9..31.....9...65..2.75..8..... initial

Autosolve

position: 2..147..98.19.34...4.2...31..847...3...6.2...6..31.9..31.7...9..8653.2.75..8..3.. autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* PRF # B1: 3,5 => SOL
* DIS # C5: 3,5 => CTR => C5: 4,7,9
* PRF # C3: 7,9 => SOL
* DIS # C3: 5 => CTR => C3: 7,9
* DIS # A5: 7,9 => CTR => A5: 1,4
* PRF # A5: 1,4 => SOL
* DIS # E3: 5,6 => CTR => E3: 8
* PRF # B2: 5,6 => SOL
* DIS # B2: 7 => CTR => B2: 5,6
* DIS # H2: 5,6 => CTR => H2: 2,7
* DIS # I2: 5,6 => CTR => I2: 2
* PRF # A5: 1,9 => SOL
* DIS # A5: 4,7 => CTR => A5: 1,9
* DIS # E5: 8 => CTR => E5: 5,9
* DIS # B4: 5,9 => CTR => B4: 2
* DIS # E5: 5,8 => CTR => E5: 9
* DIS # H6: 5,8 => CTR => H6: 2,4,7
* DIS # I6: 5,8 => CTR => I6: 2,4
* DIS # F3: 5,8 => CTR => F3: 6
* DIS # C9: 2,4 => CTR => C9: 7,9
* DIS # C9: 4,9 => CTR => C9: 2,7
* DIS # F8: 1 => CTR => F8: 4,9
* DIS # A5: 4,9 => CTR => A5: 1,7
* DIS # C9: 2,9 => CTR => C9: 4,7
* DIS # G5: 5,8 => CTR => G5: 1,7
* DIS # I6: 5,8 => CTR => I6: 2,4
* DIS # H9: 6 => CTR => H9: 1,4
* DIS # F8: 1,4 => CTR => F8: 9
* DIS # H9: 1 => CTR => H9: 4,6
* CNT  29 HDP CHAINS /  56 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 # B1: 3,5 => SOL
* STA B1: 3,5
* CNT   1 HDP CHAINS /   1 HYP OPENED

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

Details

Positions

.....7..98.1..34...4.....31..8.7...3...6.2...6...1.9..31.....9...65..2.75..8..... initial
2..147..98.19.34...4.2...31..847...3...6.2...6..31.9..31.7...9..8653.2.75..8..3.. autosolve
253147689861953472749286531928475163134692758675318924312764895486539217597821346 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (15)
C1: 3,5
A3: 7,9
E2: 5,6
A4: 1,9
F4: 5,9
F6: 5,8
C7: 2,4
A8: 4,9
E7: 2,6
F7: 4,6
E9: 2,9
G7: 5,8
I7: 5,8
H8: 1,4
I9: 4,6

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
A4,A5: 1.. / A4 = 1  =>  0 pairs (X) / A5 = 1  =>  0 pairs (_)
G4,G5: 1.. / G4 = 1  =>  0 pairs (*) / G5 = 1  =>  0 pairs (X)
F8,F9: 1.. / F8 = 1  =>  0 pairs (X) / F9 = 1  => 16 pairs (_)
H8,H9: 1.. / H8 = 1  => 16 pairs (_) / H9 = 1  =>  0 pairs (X)
A4,G4: 1.. / A4 = 1  =>  0 pairs (X) / G4 = 1  =>  0 pairs (_)
A5,G5: 1.. / A5 = 1  =>  0 pairs (*) / G5 = 1  =>  0 pairs (X)
F8,H8: 1.. / F8 = 1  =>  0 pairs (X) / H8 = 1  => 16 pairs (_)
F9,H9: 1.. / F9 = 1  => 16 pairs (_) / H9 = 1  =>  0 pairs (X)
H2,I2: 2.. / H2 = 2  =>  0 pairs (X) / I2 = 2  => 15 pairs (_)
E7,E9: 2.. / E7 = 2  =>  0 pairs (X) / E9 = 2  => 17 pairs (_)
B4,H4: 2.. / B4 = 2  => 18 pairs (_) / H4 = 2  =>  0 pairs (X)
C7,E7: 2.. / C7 = 2  => 17 pairs (_) / E7 = 2  =>  0 pairs (X)
I2,I6: 2.. / I2 = 2  => 15 pairs (_) / I6 = 2  =>  0 pairs (X)
B1,C1: 3.. / B1 = 3  =>  0 pairs (X) / C1 = 3  => 15 pairs (_)
B5,C5: 3.. / B5 = 3  => 15 pairs (_) / C5 = 3  =>  0 pairs (X)
B1,B5: 3.. / B1 = 3  =>  0 pairs (X) / B5 = 3  => 15 pairs (_)
C1,C5: 3.. / C1 = 3  => 15 pairs (_) / C5 = 3  =>  0 pairs (X)
C7,F7: 4.. / C7 = 4  =>  0 pairs (X) / F7 = 4  => 17 pairs (_)
A5,A8: 4.. / A5 = 4  =>  0 pairs (X) / A8 = 4  => 16 pairs (_)
G7,I7: 5.. / G7 = 5  => 17 pairs (_) / I7 = 5  => 16 pairs (_)
B1,B2: 6.. / B1 = 6  => 21 pairs (_) / B2 = 6  =>  0 pairs (*)
G4,H4: 6.. / G4 = 6  =>  0 pairs (X) / H4 = 6  => 20 pairs (_)
E7,F7: 6.. / E7 = 6  => 17 pairs (_) / F7 = 6  =>  0 pairs (X)
H9,I9: 6.. / H9 = 6  =>  0 pairs (X) / I9 = 6  => 16 pairs (_)
F3,F7: 6.. / F3 = 6  => 17 pairs (_) / F7 = 6  =>  0 pairs (X)
I2,I9: 6.. / I2 = 6  =>  0 pairs (X) / I9 = 6  => 16 pairs (_)
H2,G3: 7.. / H2 = 7  =>  0 pairs (*) / G3 = 7  =>  0 pairs (X)
B9,C9: 7.. / B9 = 7  =>  0 pairs (X) / C9 = 7  => 18 pairs (_)
B2,H2: 7.. / B2 = 7  =>  0 pairs (X) / H2 = 7  =>  0 pairs (_)
A3,A5: 7.. / A3 = 7  =>  0 pairs (*) / A5 = 7  =>  0 pairs (X)
G3,G5: 7.. / G3 = 7  =>  0 pairs (X) / G5 = 7  =>  0 pairs (_)
E3,F3: 8.. / E3 = 8  => 16 pairs (_) / F3 = 8  =>  0 pairs (X)
G1,H1: 8.. / G1 = 8  => 18 pairs (_) / H1 = 8  => 16 pairs (_)
E5,F6: 8.. / E5 = 8  =>  0 pairs (X) / F6 = 8  => 16 pairs (_)
G7,I7: 8.. / G7 = 8  => 16 pairs (_) / I7 = 8  => 17 pairs (_)
E3,E5: 8.. / E3 = 8  => 16 pairs (_) / E5 = 8  =>  0 pairs (X)
F3,F6: 8.. / F3 = 8  =>  0 pairs (X) / F6 = 8  => 16 pairs (_)
A3,C3: 9.. / A3 = 9  =>  0 pairs (X) / C3 = 9  =>  0 pairs (_)
F4,E5: 9.. / F4 = 9  =>  0 pairs (X) / E5 = 9  => 17 pairs (_)
A8,F8: 9.. / A8 = 9  =>  0 pairs (X) / F8 = 9  => 16 pairs (_)
E5,E9: 9.. / E5 = 9  => 17 pairs (_) / E9 = 9  =>  0 pairs (X)
* DURATION: 0:01:08.862814  START: 07:59:59.746575  END: 08:01:08.609389 2017-05-01
* CP COUNT: (41)
* SOLUTION FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A3,A4,A8,C1,C7,E2,E7,E9,F4,F6,F7,G7,H8,I7,I9)
* 2..147..98.19.34...4.2...31..847...3...6.2...6..31.9..31.7...9..8653.2.75..8..3..
* PAIR C1: 3,5 BLK 1
B1: 3,5,6                                # reduction candidate for 3,5
B1: 3,5 => SOLVED
* 253147689861953472749286531928475163134692758675318924312764895486539217597821346
B1: 6                                    # 21 pairs
* PAIR C1: 3,5 COL C
C5: 3,5,4,7,9                            # reduction candidate for 3,5
C5: 3,5 => CTR
* 2..147..98619534727492865319284751631..69275.6.431.92.312764.9.486539217597821346
C5: 4,7,9                                # 15 pairs
* PAIR A3: 7,9 BLK 1
C3: 7,9,5                                # reduction candidate for 7,9
C3: 7,9 => SOLVED
* 253147689861953472749286531928475163134692758675318924312764895486539217597821346
C3: 5 => CTR
* 2.3147..98719534..9452..73119847...37..6.21..6..31.97.31.7...9.4865392175.78213..
* PAIR A3: 7,9 COL A
A5: 7,9,1,4                              # reduction candidate for 7,9
A5: 7,9 => CTR
* 2..147..98.19.34...4.2..7311984756237..6921..62.31897.3127...9.4865392175..8213..
A5: 1,4 => SOLVED
* 253147689861953472749286531928475163134692758675318924312764895486539217597821346
* PAIR E2: 5,6 BLK 2
E3: 5,6,8                                # reduction candidate for 5,6
E3: 5,6 => CTR
* 235147..98619534727492685311584796.3.93682...6..3159..314726.9.98653.2.75..89.3..
E3: 8                                    # 16 pairs
F3: 5,6,8                                # reduction candidate for 5,6
F3: 5,6                                  # 16 pairs
* PAIR E2: 5,6 ROW 2
B2: 5,6,7                                # reduction candidate for 5,6
B2: 5,6 => SOLVED
* 253147689861953472749286531928475163134692758675318924312764895486539217597821346
B2: 7 => CTR
* 263147..98719534..9452..73119847.6.373.6.21..6..31.97.31.7...9.4865392175.78213..
H2: 5,6,2,7                              # reduction candidate for 5,6
H2: 5,6 => CTR
* 263147..98719534629452..73119847...37..6.21..6..31.97.31.7...9.4865392175.78213.6
H2: 2,7                                  # 16 pairs
I2: 5,6,2                                # reduction candidate for 5,6
I2: 5,6 => CTR
* 2..147..98.19.342..4.2..731.2847...37..6.21..654318972312764.9.4865392175.78213..
I2: 2                                    # 15 pairs
* PAIR A4: 1,9 BLK 4
A5: 1,9,4,7                              # reduction candidate for 1,9
A5: 1,9 => SOLVED
* 253147689861953472749286531928475163134692758675318924312764895486539217597821346
A5: 4,7 => CTR
* 2..147..98719.34..9452..73119847...37..6.21..6..31.97.31.7...9.4865392175.78213..
* PAIR F4: 5,9 BLK 5
E5: 5,9,8                                # reduction candidate for 5,9
E5: 8 => CTR
* 2..147..98.19.34..7492.8.311.8479..34..682...6..3159..31.7...9.98653.2.75..89.3..
E5: 5,9                                  # 16 pairs
* PAIR F4: 5,9 ROW 4
B4: 5,9,2                                # reduction candidate for 5,9
B4: 5,9 => CTR
* 2..147..98719.34.29452..73119847.6237..6.21..6..31.97.31.7...9.4865392175.7821346
B4: 2                                    # 18 pairs
* PAIR F6: 5,8 BLK 5
E5: 5,8,9                                # reduction candidate for 5,8
E5: 5,8 => CTR
* 2..147..98.19.34..7492...311.8479..34..6.2...6..31.9..31.7...9.98653.2.75..89.3..
E5: 9                                    # 17 pairs
* PAIR F6: 5,8 ROW 6
H6: 5,8,2,4,7                            # reduction candidate for 5,8
H6: 5,8 => CTR
* 2..147..98.19.34727492...31..847..23...6.27..6..31.9..31.7...9..8653.2.75..8..3.6
H6: 2,4,7                                # 15 pairs
I6: 5,8,2,4                              # reduction candidate for 5,8
I6: 5,8 => CTR
* 2..147.598.19534.2.45286731..8475..3753692..46.43189.53127645984865392175..821346
I6: 2,4                                  # 16 pairs
* PAIR F6: 5,8 COL F
F3: 5,8,6                                # reduction candidate for 5,8
F3: 5,8 => CTR
* 2..147..98.19.34..7492...311.8479..34..6.2...6..31.9..314726.9.98653.2.75..89.3..
F3: 6                                    # 17 pairs
* PAIR C7: 2,4 BLK 7
C9: 2,4,7,9                              # reduction candidate for 2,4
C9: 2,4 => CTR
* 2..147..98.19.3472.4.2...31..847...3...6.27..6.731.9..31.7...9.98653.2.757.8..3.6
C9: 7,9                                  # 17 pairs
* PAIR C7: 2,4 COL C
C6: 2,4,5,7                              # reduction candidate for 2,4
C6: 5,7                                  # 20 pairs
C6: 2,4                                  # 18 pairs
* PAIR A8: 4,9 BLK 7
C9: 4,9,2,7                              # reduction candidate for 4,9
C9: 4,9 => CTR
* 2..147..9861953472749286531.984751.3...6927..6.73189..312764.9..8653.2.757.82.3.6
C9: 2,7                                  # 16 pairs
* PAIR A8: 4,9 ROW 8
F8: 4,9,1                                # reduction candidate for 4,9
F8: 1 => CTR
* 2..147..98.19.34..7492...311.847...34..6.2...6..31.9..31.7...9.9865312475..8..316
F8: 4,9                                  # 16 pairs
* PAIR A8: 4,9 COL A
A5: 4,9,1,7                              # reduction candidate for 4,9
A5: 4,9 => CTR
* 2..147..98.19.34..7492...311.847...3...6.2...6..31.9..31.7...9..8653.2.75..8..3..
A5: 1,7                                  # 16 pairs
* PAIR E9: 2,9 ROW 9
B9: 2,9,7                                # reduction candidate for 2,9
B9: 2,9                                  # 18 pairs
C9: 2,9,4,7                              # reduction candidate for 2,9
C9: 2,9 => CTR
* 2..147..98.19.34727492...31..847.1631.46.27..6.731.9243127...9..8653.2.757.8..3.6
C9: 4,7                                  # 16 pairs
* PAIR G7: 5,8 COL G
G1: 5,8,6                                # reduction candidate for 5,8
G1: 5,8                                  # 19 pairs
G5: 5,8,1,7                              # reduction candidate for 5,8
G5: 5,8 => CTR
* 2..147..98.19.34...4.2..731..847.163...6.2...6..31.9..31.7...9..8653.2.75..8..3..
G5: 1,7                                  # 16 pairs
* PAIR I7: 5,8 COL I
I5: 5,8,4                                # reduction candidate for 5,8
I5: 5,8                                  # 18 pairs
I6: 5,8,2,4                              # reduction candidate for 5,8
I6: 5,8 => CTR
* 2..147.598.19534.2.45286731..8475..3753692..46.43189.53127645984865392175..821346
I6: 2,4                                  # 16 pairs
* PAIR H8: 1,4 BLK 9
H9: 1,4,6                                # reduction candidate for 1,4
H9: 6 => CTR
* 263147..98.1953426.452..7311284796537..6.21..6..31.9.231.7...9..8653.2175..8.1364
H9: 1,4                                  # 16 pairs
* PAIR H8: 1,4 ROW 8
F8: 1,4,9                                # reduction candidate for 1,4
F8: 1,4 => CTR
* 2..147..98.19.34..7492...311.847...34..6.2...6..31.9..31.7...9.98653.2.75..8..3..
F8: 9                                    # 16 pairs
* PAIR I9: 4,6 BLK 9
H9: 4,6,1                                # reduction candidate for 4,6
H9: 1 => CTR
* 2..147..98.19.34.27492...311.847...34..6.21..6..31.9.431.7...9.9865312475..8..316
H9: 4,6                                  # 16 pairs
* INCONCLUSIVE
* SAVE PR GRAPH zz-sudoku-de-703274-base-pr-000.dot
* REASONING
* PRF # B1: 3,5 => SOL
* DIS # C5: 3,5 => CTR => C5: 4,7,9
* PRF # C3: 7,9 => SOL
* DIS # C3: 5 => CTR => C3: 7,9
* DIS # A5: 7,9 => CTR => A5: 1,4
* PRF # A5: 1,4 => SOL
* DIS # E3: 5,6 => CTR => E3: 8
* PRF # B2: 5,6 => SOL
* DIS # B2: 7 => CTR => B2: 5,6
* DIS # H2: 5,6 => CTR => H2: 2,7
* DIS # I2: 5,6 => CTR => I2: 2
* PRF # A5: 1,9 => SOL
* DIS # A5: 4,7 => CTR => A5: 1,9
* DIS # E5: 8 => CTR => E5: 5,9
* DIS # B4: 5,9 => CTR => B4: 2
* DIS # E5: 5,8 => CTR => E5: 9
* DIS # H6: 5,8 => CTR => H6: 2,4,7
* DIS # I6: 5,8 => CTR => I6: 2,4
* DIS # F3: 5,8 => CTR => F3: 6
* DIS # C9: 2,4 => CTR => C9: 7,9
* DIS # C9: 4,9 => CTR => C9: 2,7
* DIS # F8: 1 => CTR => F8: 4,9
* DIS # A5: 4,9 => CTR => A5: 1,7
* DIS # C9: 2,9 => CTR => C9: 4,7
* DIS # G5: 5,8 => CTR => G5: 1,7
* DIS # I6: 5,8 => CTR => I6: 2,4
* DIS # H9: 6 => CTR => H9: 1,4
* DIS # F8: 1,4 => CTR => F8: 9
* DIS # H9: 1 => CTR => H9: 4,6
* CNT  29 HDP CHAINS /  56 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A3,A4,A8,C1,C7,E2,E7,E9,F4,F6,F7,G7,H8,I7,I9)
* 2..147..98.19.34...4.2...31..847...3...6.2...6..31.9..31.7...9..8653.2.75..8..3..
* PAIR C1: 3,5 BLK 1
B1: 3,5,6                                # reduction candidate for 3,5
B1: 3,5 => SOLVED
* 253147689861953472749286531928475163134692758675318924312764895486539217597821346
* DURATION: 0:00:02.343195  START: 08:02:00.528861  END: 08:02:02.872056 2017-05-01
* SOLUTION FOUND
* SAVE PR GRAPH zz-sudoku-de-703274-base-pr-001.dot
* REASONING
* PRF # B1: 3,5 => SOL
* STA B1: 3,5
* CNT   1 HDP CHAINS /   1 HYP OPENED

Header Info

http://www.sudokus.de/703274.html
sehr schwierig

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

* PAIR REDUCTION ..
* ROUND 1: 2..147..98.19.34...4.2...31..847...3...6.2...6..31.9..31.7...9..8653.2.75..8..3..
C1: 3,5
B1: 3,5,6                                # reduction candidate for 3,5
B1: 3,5 => SOLVED
* 253147689861953472749286531928475163134692758675318924312764895486539217597821346
* SOLVED!
--------------------------------------------------

* AUTO ..
A1 = 2                # set value
D1 = 1                # set value
D6 = 3                # set value
D7 = 7                # set value
B8 = 8                # set value
E8 = 3                # set value
G9 = 3                # set value
E1: 4..               # hidden single
D4: 4..               # hidden single
E1 = 4                # set value
D4 = 4                # set value
D2: 9                 # naked single
Q3: 2.. = H2,I2: 2.. => D2,E2 != 2
Q2: 8.. = E3,F3: 8.. => G3 != 8
Q8: 2.. = E7,E9: 2.. => E3 != 2
Q5,Q8: 9.. => E2,E3,F3 != 9
Q9: 1.. = H8,H9: 1.. => H4,H5 != 1
D3: 2..               # hidden single
D2 = 9                # set value
D3: 2                 # naked single
D3 = 2                # set value
G7,I7: 5,8.. => G7,I7 != 4,6 # hidden pair
Q9: 6.. = H9,I9: 6.. => E9,F9 != 6
* UNSOLVED!

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

* DISABLE VALUE:: B1 != 6
B2: 6..               # hidden single

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

Solution

position: 253147689861953472749286531928475163134692758675318924312764895486539217597821346 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:

* PRF # B1: 3,5 => SOL
* INC # B1: 6 => UNS
* DIS # C5: 3,5 => CTR => C5: 4,7,9
* INC # C5: 4,7,9 => UNS
* PRF # C3: 7,9 => SOL
* DIS # C3: 5 => CTR => C3: 7,9
* DIS # A5: 7,9 => CTR => A5: 1,4
* PRF # A5: 1,4 => SOL
* DIS # E3: 5,6 => CTR => E3: 8
* INC # E3: 8 => UNS
* INC # F3: 5,6 => UNS
* PRF # B2: 5,6 => SOL
* DIS # B2: 7 => CTR => B2: 5,6
* DIS # H2: 5,6 => CTR => H2: 2,7
* INC # H2: 2,7 => UNS
* DIS # I2: 5,6 => CTR => I2: 2
* INC # I2: 2 => UNS
* PRF # A5: 1,9 => SOL
* DIS # A5: 4,7 => CTR => A5: 1,9
* INC # E5: 5,9 => UNS
* DIS # E5: 8 => CTR => E5: 5,9
* DIS # B4: 5,9 => CTR => B4: 2
* INC # B4: 2 => UNS
* DIS # E5: 5,8 => CTR => E5: 9
* INC # E5: 9 => UNS
* DIS # H6: 5,8 => CTR => H6: 2,4,7
* INC # H6: 2,4,7 => UNS
* DIS # I6: 5,8 => CTR => I6: 2,4
* INC # I6: 2,4 => UNS
* DIS # F3: 5,8 => CTR => F3: 6
* INC # F3: 6 => UNS
* DIS # C9: 2,4 => CTR => C9: 7,9
* INC # C9: 7,9 => UNS
* INC # C6: 2,4 => UNS
* INC # C6: 5,7 => UNS
* DIS # C9: 4,9 => CTR => C9: 2,7
* INC # C9: 2,7 => UNS
* INC # F8: 4,9 => UNS
* DIS # F8: 1 => CTR => F8: 4,9
* DIS # A5: 4,9 => CTR => A5: 1,7
* INC # A5: 1,7 => UNS
* INC # B9: 2,9 => UNS
* DIS # C9: 2,9 => CTR => C9: 4,7
* INC # C9: 4,7 => UNS
* INC # G1: 5,8 => UNS
* DIS # G5: 5,8 => CTR => G5: 1,7
* INC # G5: 1,7 => UNS
* INC # I5: 5,8 => UNS
* DIS # I6: 5,8 => CTR => I6: 2,4
* INC # I6: 2,4 => UNS
* INC # H9: 1,4 => UNS
* DIS # H9: 6 => CTR => H9: 1,4
* DIS # F8: 1,4 => CTR => F8: 9
* INC # F8: 9 => UNS
* INC # H9: 4,6 => UNS
* DIS # H9: 1 => CTR => H9: 4,6
* CNT  56 HDP CHAINS /  56 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* PRF # B1: 3,5 => SOL
* STA B1: 3,5
* CNT   1 HDP CHAINS /   1 HYP OPENED