Analysis of zz-sudoku-de-702316-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: ..4....8.63.....54..97..63.4...36.9.....7.....2.98...5.41..25..78.....46.6....9.. initial

Autosolve

position: .746.3.8963.1..754..97..63.4...36.97.96.7.....2798..65941.6257.78.....46.6...79.. autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* DIS # A3: 1,5 => CTR => A3: 2,8
* DIS # A3: 1,5 => CTR => A3: 2,8
* DIS # E3: 2,5 => CTR => E3: 4
* PRF # E3: 4 => SOL
* DIS # A1: 2,5 => CTR => A1: 1
* PRF # A1: 1 => SOL
* DIS # A1: 5 => CTR => A1: 1,2
* DIS # G4: 1,2 => CTR => G4: 8
* PRF # G4: 8 => SOL
* DIS # G5: 1,2 => CTR => G5: 3,4,8
* PRF # G8: 1,2 => SOL
* DIS # G8: 3 => CTR => G8: 1,2
* PRF # A3: 1,2 => SOL
* PRF # I5: 1,2 => SOL
* DIS # I5: 3 => CTR => I5: 1,2
* DIS # I9: 1,2 => CTR => I9: 3,8
* PRF # I9: 3,8 => SOL
* DIS # A5: 1,5 => CTR => A5: 3,8
* DIS # A5: 1,3 => CTR => A5: 5,8
* DIS # A5: 1,3 => CTR => A5: 5,8
* DIS # G6: 1,3 => CTR => G6: 4
* PRF # D5: 2,5 => SOL
* DIS # D5: 4 => CTR => D5: 2,5
* PRF # F5: 1,4 => SOL
* DIS # F5: 5 => CTR => F5: 1,4
* DIS # G6: 3 => CTR => G6: 1,4
* DIS # G4: 1,2 => CTR => G4: 8
* PRF # G4: 8 => SOL
* DIS # G5: 1,2 => CTR => G5: 3,4,8
* PRF # I5: 1,2 => SOL
* DIS # I5: 3 => CTR => I5: 1,2
* DIS # C9: 2,5 => CTR => C9: 3
* DIS # A1: 2,5 => CTR => A1: 1
* PRF # A1: 1 => SOL
* PRF # A3: 2,5 => SOL
* DIS # D9: 3,8 => CTR => D9: 4,5
* PRF # D9: 4,5 => SOL
* DIS # D9: 3,5 => CTR => D9: 4,8
* DIS # C8: 3,5 => CTR => C8: 2
* PRF # C8: 2 => SOL
* PRF # E8: 5,9 => SOL
* DIS # E8: 1 => CTR => E8: 5,9
* PRF # I9: 3,8 => SOL
* DIS # I9: 1,2 => CTR => I9: 3,8
* PRF # G8: 1,2 => SOL
* DIS # G8: 3 => CTR => G8: 1,2
* DIS # I9: 1,2 => CTR => I9: 3,8
* PRF # I9: 3,8 => SOL
* CNT  48 HDP CHAINS /  64 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 # A3: 1,5 => CTR => A3: 2,8
* DIS A3: 2,8 # E3: 2,5 => CTR => E3: 4
* PRF A3: 2,8 + E3: 4 => SOL
* STA A3: 2,8 + E3: 4
* CNT   3 HDP CHAINS /   3 HYP OPENED

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

Details

Positions

..4....8.63.....54..97..63.4...36.9.....7.....2.98...5.41..25..78.....46.6....9.. initial
.746.3.8963.1..754..97..63.4...36.97.96.7.....2798..65941.6257.78.....46.6...79.. autosolve
174653289638129754259748631415236897896574312327981465941862573782395146563417928 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (19)
C2: 2,8
B3: 1,5
E1: 2,5
E2: 2,9
F2: 8,9
G1: 1,2
I3: 1,2
B4: 1,5
C4: 5,8
A6: 1,3
D4: 2,5
F6: 1,4
H5: 1,2
A9: 2,5
D7: 3,8
D8: 3,5
F8: 5,9
I7: 3,8
H9: 1,2

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
G1,I3: 1.. / G1 = 1  =>  0 pairs (X) / I3 = 1  =>  0 pairs (_)
F5,F6: 1.. / F5 = 1  =>  0 pairs (X) / F6 = 1  => 18 pairs (_)
E8,E9: 1.. / E8 = 1  =>  0 pairs (X) / E9 = 1  =>  0 pairs (_)
A1,G1: 1.. / A1 = 1  =>  0 pairs (*) / G1 = 1  =>  0 pairs (X)
B4,G4: 1.. / B4 = 1  => 23 pairs (_) / G4 = 1  =>  0 pairs (X)
E8,G8: 1.. / E8 = 1  =>  0 pairs (X) / G8 = 1  =>  0 pairs (_)
B3,B4: 1.. / B3 = 1  =>  0 pairs (X) / B4 = 1  => 23 pairs (_)
H5,H9: 1.. / H5 = 1  =>  0 pairs (*) / H9 = 1  =>  0 pairs (X)
G1,I3: 2.. / G1 = 2  =>  0 pairs (*) / I3 = 2  =>  0 pairs (X)
D4,D5: 2.. / D4 = 2  => 20 pairs (_) / D5 = 2  =>  0 pairs (X)
C2,E2: 2.. / C2 = 2  =>  0 pairs (X) / E2 = 2  =>  0 pairs (_)
D4,G4: 2.. / D4 = 2  => 20 pairs (_) / G4 = 2  =>  0 pairs (X)
C8,G8: 2.. / C8 = 2  =>  0 pairs (*) / G8 = 2  =>  0 pairs (X)
H5,H9: 2.. / H5 = 2  =>  0 pairs (X) / H9 = 2  =>  0 pairs (_)
A5,A6: 3.. / A5 = 3  =>  0 pairs (X) / A6 = 3  => 19 pairs (_)
C8,C9: 3.. / C8 = 3  =>  0 pairs (X) / C9 = 3  => 20 pairs (_)
A6,G6: 3.. / A6 = 3  => 19 pairs (_) / G6 = 3  =>  0 pairs (X)
D7,I7: 3.. / D7 = 3  =>  0 pairs (X) / I7 = 3  =>  0 pairs (_)
E3,F3: 4.. / E3 = 4  =>  0 pairs (*) / F3 = 4  =>  0 pairs (X)
G5,G6: 4.. / G5 = 4  =>  0 pairs (X) / G6 = 4  => 18 pairs (_)
D9,E9: 4.. / D9 = 4  =>  0 pairs (*) / E9 = 4  =>  0 pairs (X)
F6,G6: 4.. / F6 = 4  =>  0 pairs (X) / G6 = 4  => 18 pairs (_)
D5,D9: 4.. / D5 = 4  =>  0 pairs (X) / D9 = 4  =>  0 pairs (_)
E3,E9: 4.. / E3 = 4  =>  0 pairs (*) / E9 = 4  =>  0 pairs (X)
A1,E1: 5.. / A1 = 5  =>  0 pairs (X) / E1 = 5  => 23 pairs (_)
B3,B4: 5.. / B3 = 5  => 23 pairs (_) / B4 = 5  =>  0 pairs (X)
C2,A3: 8.. / C2 = 8  =>  0 pairs (*) / A3 = 8  =>  0 pairs (X)
F2,F3: 8.. / F2 = 8  =>  0 pairs (X) / F3 = 8  =>  0 pairs (_)
C4,A5: 8.. / C4 = 8  =>  0 pairs (X) / A5 = 8  =>  0 pairs (_)
G4,G5: 8.. / G4 = 8  =>  0 pairs (*) / G5 = 8  =>  0 pairs (X)
D7,D9: 8.. / D7 = 8  =>  0 pairs (*) / D9 = 8  =>  0 pairs (X)
I7,I9: 8.. / I7 = 8  =>  0 pairs (X) / I9 = 8  =>  0 pairs (_)
C2,F2: 8.. / C2 = 8  =>  0 pairs (*) / F2 = 8  =>  0 pairs (X)
A3,F3: 8.. / A3 = 8  =>  0 pairs (X) / F3 = 8  =>  0 pairs (_)
C4,G4: 8.. / C4 = 8  =>  0 pairs (X) / G4 = 8  =>  0 pairs (_)
A5,G5: 8.. / A5 = 8  =>  0 pairs (*) / G5 = 8  =>  0 pairs (X)
D7,I7: 8.. / D7 = 8  =>  0 pairs (*) / I7 = 8  =>  0 pairs (X)
D9,I9: 8.. / D9 = 8  =>  0 pairs (X) / I9 = 8  =>  0 pairs (_)
A3,A5: 8.. / A3 = 8  =>  0 pairs (X) / A5 = 8  =>  0 pairs (_)
C2,C4: 8.. / C2 = 8  =>  0 pairs (*) / C4 = 8  =>  0 pairs (X)
E2,F2: 9.. / E2 = 9  =>  0 pairs (X) / F2 = 9  =>  0 pairs (_)
E8,F8: 9.. / E8 = 9  =>  0 pairs (*) / F8 = 9  =>  0 pairs (X)
E2,E8: 9.. / E2 = 9  =>  0 pairs (X) / E8 = 9  =>  0 pairs (_)
F2,F8: 9.. / F2 = 9  =>  0 pairs (*) / F8 = 9  =>  0 pairs (X)
* DURATION: 0:01:13.423098  START: 07:57:17.128012  END: 07:58:30.551110 2017-05-01
* CP COUNT: (44)
* SOLUTION FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A6,A9,B3,B4,C2,C4,D4,D7,D8,E1,E2,F2,F6,F8,G1,H5,H9,I3,I7)
* .746.3.8963.1..754..97..63.4...36.97.96.7.....2798..65941.6257.78.....46.6...79..
* PAIR C2: 2,8 BLK 1
A3: 2,8,1,5                              # reduction candidate for 2,8
A3: 1,5 => CTR
* .746.3.89638129754..97.86324.5236897896.7....32798..65941.6257.78..95146.6...79..
A3: 2,8                                  # 21 pairs
* PAIR B3: 1,5 BLK 1
A1: 1,5,2                                # reduction candidate for 1,5
A1: 1,5                                  # 21 pairs
A3: 1,5,2,8                              # reduction candidate for 1,5
A3: 1,5 => CTR
* .746.3.89638129754..97.86324.5236897896.7....32798..65941.6257.78..95146.6...79..
A3: 2,8                                  # 21 pairs
* PAIR E1: 2,5 BLK 2
E3: 2,5,4                                # reduction candidate for 2,5
E3: 2,5 => CTR
* .746.3.8963.1.87548.97.463.4.823619719647582332798146594136257878.519346.6..479..
E3: 4 => SOLVED
* 174653289638129754259748631415236897896574312327981465941862573782395146563417928
* PAIR E1: 2,5 ROW 1
A1: 2,5,1                                # reduction candidate for 2,5
A1: 2,5 => CTR
* .746.318963.198754..97..63241..36.97.96.7....327981465941.6257.78..19.46.6...79..
A1: 1 => SOLVED
* 174653289638129754259748631415236897896574312327981465941862573782395146563417928
* PAIR G1: 1,2 ROW 1
A1: 1,2,5                                # reduction candidate for 1,2
A1: 5 => CTR
* 5746231896321987548197..63.4...36.97.96.7.....2798..65941.6257.78.....46.6...79..
A1: 1,2                                  # 23 pairs
* PAIR G1: 1,2 COL G
G4: 1,2,8                                # reduction candidate for 1,2
G4: 1,2 => CTR
* .746.3.8963.1..754..97..63.4.8.36.97.96.7.8...2798.465941.6257.78....346.63..79..
G4: 8 => SOLVED
* 174653289638129754259748631415236897896574312327981465941862573782395146563417928
G5: 1,2,3,4,8                            # reduction candidate for 1,2
G5: 1,2 => CTR
* .746.3.8963.1..754..97..63.4...36897896.7...332798.46594136257878.5.9346.638479..
G5: 3,4,8                                # 19 pairs
G8: 1,2,3                                # reduction candidate for 1,2
G8: 1,2 => SOLVED
* 174653289638129754259748631415236897896574312327981465941862573782395146563417928
G8: 3 => CTR
* .746.3.8963.1..754..97..63.4...36.97.96.7.....2798..65941.6257.782.19346563.479..
* PAIR I3: 1,2 ROW 3
A3: 1,2,5,8                              # reduction candidate for 1,2
A3: 1,2 => SOLVED
* 174653289638129754259748631415236897896574312327981465941862573782395146563417928
A3: 5,8                                  # 20 pairs
* PAIR I3: 1,2 COL I
I5: 1,2,3                                # reduction candidate for 1,2
I5: 1,2 => SOLVED
* 174653289638129754259748631415236897896574312327981465941862573782395146563417928
I5: 3 => CTR
* .746.3.8963.1987548.97.463.4...36.97.96.7...332798..6594136257878.5.9346.638479..
I9: 1,2,3,8                              # reduction candidate for 1,2
I9: 1,2 => CTR
* .746.3.8963.1..754..97.463.4...36.97.9647...33279814659413625787825193465638479..
I9: 3,8 => SOLVED
* 174653289638129754259748631415236897896574312327981465941862573782395146563417928
* PAIR B4: 1,5 BLK 4
A5: 1,5,3,8                              # reduction candidate for 1,5
A5: 1,5 => CTR
* .746.3.8963.1..7548.97..63.4.8.36.97.96.7.8.332798.46594136257878.5.9346.6...79..
A5: 3,8                                  # 21 pairs
* PAIR C4: 5,8 BLK 4
A5: 5,8,1,3                              # reduction candidate for 5,8
A5: 1,3 => CTR
* .746.3.8963.1..7548.97..63.4.8.36.97.96.7.8...2798.465941.6257.78....346.63..79..
A5: 5,8                                  # 23 pairs
* PAIR A6: 1,3 BLK 4
A5: 1,3,5,8                              # reduction candidate for 1,3
A5: 1,3 => CTR
* .746.3.8963.1..7548.97..63.4.8.36.97.96.7.8...2798.465941.6257.78....346.63..79..
A5: 5,8                                  # 23 pairs
* PAIR A6: 1,3 ROW 6
G6: 1,3,4                                # reduction candidate for 1,3
G6: 1,3 => CTR
* .746.3.8963.1..754..974.63.4...36897896.71423.27984.65941.6257.78.....46.6.4.79.8
G6: 4                                    # 18 pairs
* PAIR D4: 2,5 BLK 5
D5: 2,5,4                                # reduction candidate for 2,5
D5: 2,5 => SOLVED
* 174653289638129754259748631415236897896574312327981465941862573782395146563417928
D5: 4 => CTR
* .746.3.8963.1987548.97.463.4.823619719647582332798146594136257878.519346.6..479..
* PAIR F6: 1,4 BLK 5
F5: 1,4,5                                # reduction candidate for 1,4
F5: 1,4 => SOLVED
* 174653289638129754259748631415236897896574312327981465941862573782395146563417928
F5: 5 => CTR
* .746.3.8963.1987548.97.463.4.823619719647582332798146594136257878.519346.6...79..
* PAIR F6: 1,4 ROW 6
G6: 1,4,3                                # reduction candidate for 1,4
G6: 3 => CTR
* .746.3.8963.1..754..97..63.4...36.97.96.7.4...27984365941.6257.78.....46.6.4.79.8
G6: 1,4                                  # 19 pairs
* PAIR H5: 1,2 BLK 6
G4: 1,2,8                                # reduction candidate for 1,2
G4: 1,2 => CTR
* .746.3.8963.1..754..97..63.4.8.36.97.96.7.8...2798.465941.6257.78....346.63..79..
G4: 8 => SOLVED
* 174653289638129754259748631415236897896574312327981465941862573782395146563417928
G5: 1,2,3,4,8                            # reduction candidate for 1,2
G5: 1,2 => CTR
* .746.3.8963.1..754..97..63.4...36897896.7...332798.46594136257878.5.9346.638479..
G5: 3,4,8                                # 19 pairs
I5: 1,2,3                                # reduction candidate for 1,2
I5: 1,2 => SOLVED
* 174653289638129754259748631415236897896574312327981465941862573782395146563417928
I5: 3 => CTR
* .746.3.8963.1987548.97.463.4...36.97.96.7...332798..6594136257878.5.9346.638479..
* PAIR A9: 2,5 BLK 7
C8: 2,5,3                                # reduction candidate for 2,5
C8: 2,5                                  # 20 pairs
C9: 2,5,3                                # reduction candidate for 2,5
C9: 2,5 => CTR
* .746.318963.1987548197..632458.36.97.96.7.....2798..65941.6257.7835.9246.6...791.
C9: 3                                    # 20 pairs
* PAIR A9: 2,5 COL A
A1: 2,5,1                                # reduction candidate for 2,5
A1: 2,5 => CTR
* .746.318963.198754..97..63241..36.97.96.7....327981465941.6257.78..19.46.6...79..
A1: 1 => SOLVED
* 174653289638129754259748631415236897896574312327981465941862573782395146563417928
A3: 2,5,1,8                              # reduction candidate for 2,5
A3: 2,5 => SOLVED
* 174653289638129754259748631415236897896574312327981465941862573782395146563417928
A3: 1,8                                  # 20 pairs
* PAIR D7: 3,8 BLK 8
D9: 3,8,4,5                              # reduction candidate for 3,8
D9: 3,8 => CTR
* .746.3.8963.1987548.97.463.4.823619719647582332798146594136257878.519346.6..479..
D9: 4,5 => SOLVED
* 174653289638129754259748631415236897896574312327981465941862573782395146563417928
* PAIR D8: 3,5 BLK 8
D9: 3,5,4,8                              # reduction candidate for 3,5
D9: 3,5 => CTR
* .746.318963.198754819754632458236.97.964753..32798146594186257378..19246.6..47918
D9: 4,8                                  # 20 pairs
* PAIR D8: 3,5 ROW 8
C8: 3,5,2                                # reduction candidate for 3,5
C8: 3,5 => CTR
* .746.31896381..754..97..63241.236897896.7..21327981465941.6257.78..19246.6...791.
C8: 2 => SOLVED
* 174653289638129754259748631415236897896574312327981465941862573782395146563417928
* PAIR F8: 5,9 BLK 8
E8: 5,9,1                                # reduction candidate for 5,9
E8: 5,9 => SOLVED
* 174653289638129754259748631415236897896574312327981465941862573782395146563417928
E8: 1 => CTR
* .746.3.8963.1987548.97..63.4.8.36.97.96.7.8...2798.465941.6257.78..19346.63..79..
* PAIR I7: 3,8 BLK 9
I9: 3,8,1,2                              # reduction candidate for 3,8
I9: 3,8 => SOLVED
* 174653289638129754259748631415236897896574312327981465941862573782395146563417928
I9: 1,2 => CTR
* .746.3.8963.1..754..97.463.4...36.97.9647...33279814659413625787825193465638479..
* PAIR H9: 1,2 BLK 9
G8: 1,2,3                                # reduction candidate for 1,2
G8: 1,2 => SOLVED
* 174653289638129754259748631415236897896574312327981465941862573782395146563417928
G8: 3 => CTR
* .746.3.8963.1..754..97..63.4...36.97.96.7.....2798..65941.6257.782.19346563.479..
I9: 1,2,3,8                              # reduction candidate for 1,2
I9: 1,2 => CTR
* .746.3.8963.1..754..97.463.4...36.97.9647...33279814659413625787825193465638479..
I9: 3,8 => SOLVED
* 174653289638129754259748631415236897896574312327981465941862573782395146563417928
* INCONCLUSIVE
* SAVE PR GRAPH zz-sudoku-de-702316-base-pr-000.dot
* REASONING
* DIS # A3: 1,5 => CTR => A3: 2,8
* DIS # A3: 1,5 => CTR => A3: 2,8
* DIS # E3: 2,5 => CTR => E3: 4
* PRF # E3: 4 => SOL
* DIS # A1: 2,5 => CTR => A1: 1
* PRF # A1: 1 => SOL
* DIS # A1: 5 => CTR => A1: 1,2
* DIS # G4: 1,2 => CTR => G4: 8
* PRF # G4: 8 => SOL
* DIS # G5: 1,2 => CTR => G5: 3,4,8
* PRF # G8: 1,2 => SOL
* DIS # G8: 3 => CTR => G8: 1,2
* PRF # A3: 1,2 => SOL
* PRF # I5: 1,2 => SOL
* DIS # I5: 3 => CTR => I5: 1,2
* DIS # I9: 1,2 => CTR => I9: 3,8
* PRF # I9: 3,8 => SOL
* DIS # A5: 1,5 => CTR => A5: 3,8
* DIS # A5: 1,3 => CTR => A5: 5,8
* DIS # A5: 1,3 => CTR => A5: 5,8
* DIS # G6: 1,3 => CTR => G6: 4
* PRF # D5: 2,5 => SOL
* DIS # D5: 4 => CTR => D5: 2,5
* PRF # F5: 1,4 => SOL
* DIS # F5: 5 => CTR => F5: 1,4
* DIS # G6: 3 => CTR => G6: 1,4
* DIS # G4: 1,2 => CTR => G4: 8
* PRF # G4: 8 => SOL
* DIS # G5: 1,2 => CTR => G5: 3,4,8
* PRF # I5: 1,2 => SOL
* DIS # I5: 3 => CTR => I5: 1,2
* DIS # C9: 2,5 => CTR => C9: 3
* DIS # A1: 2,5 => CTR => A1: 1
* PRF # A1: 1 => SOL
* PRF # A3: 2,5 => SOL
* DIS # D9: 3,8 => CTR => D9: 4,5
* PRF # D9: 4,5 => SOL
* DIS # D9: 3,5 => CTR => D9: 4,8
* DIS # C8: 3,5 => CTR => C8: 2
* PRF # C8: 2 => SOL
* PRF # E8: 5,9 => SOL
* DIS # E8: 1 => CTR => E8: 5,9
* PRF # I9: 3,8 => SOL
* DIS # I9: 1,2 => CTR => I9: 3,8
* PRF # G8: 1,2 => SOL
* DIS # G8: 3 => CTR => G8: 1,2
* DIS # I9: 1,2 => CTR => I9: 3,8
* PRF # I9: 3,8 => SOL
* CNT  48 HDP CHAINS /  64 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A6,A9,B3,B4,C2,C4,D4,D7,D8,E1,E2,F2,F6,F8,G1,H5,H9,I3,I7)
* .746.3.8963.1..754..97..63.4...36.97.96.7.....2798..65941.6257.78.....46.6...79..
* PAIR C2: 2,8 BLK 1
A3: 2,8,1,5                              # reduction candidate for 2,8
A3: 1,5 => CTR
* .746.3.89638129754..97.86324.5236897896.7....32798..65941.6257.78..95146.6...79..
* PAIR E1: 2,5 BLK 2
E3: 2,5,4                                # reduction candidate for 2,5
E3: 2,5 => CTR
* .746.3.8963.1.87548.97.463.4.823619719647582332798146594136257878.51934626..479..
E3: 4 => SOLVED
* 174653289638129754259748631415236897896574312327981465941862573782395146563417928
* DURATION: 0:00:05.895447  START: 07:59:36.582639  END: 07:59:42.478086 2017-05-01
* SOLUTION FOUND
* SAVE PR GRAPH zz-sudoku-de-702316-base-pr-001.dot
* REASONING
* DIS # A3: 1,5 => CTR => A3: 2,8
* DIS A3: 2,8 # E3: 2,5 => CTR => E3: 4
* PRF A3: 2,8 + E3: 4 => SOL
* STA A3: 2,8 + E3: 4
* CNT   3 HDP CHAINS /   3 HYP OPENED

Header Info

http://www.sudokus.de/702316.html
sehr schwierig

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

* PAIR REDUCTION ..
* ROUND 1: .746.3.8963.1..754..97..63.4...36.97.96.7.....2798..65941.6257.78.....46.6...79..
C2: 2,8
A3: 1,2,5,8                              # reduction candidate for 2,8
A3: 1,5 => CTR
* .746.3.89638129754..97.86324.5236897896.7....32798..65941.6257.78..95146.6...79..
B3: 1,5
E1: 2,5
E3: 2,4,5                                # reduction candidate for 2,5
E3: 2,5 => CTR
* .746.3.8963.1.87548.97.463.4.823619719647582332798146594136257878.51934626..479..
E3: 4 => SOLVED
* 174653289638129754259748631415236897896574312327981465941862573782395146563417928
* SOLVED!
--------------------------------------------------

--------------------------------------------------
* AUTO ..
Q1,Q3: 1.. => E1,E3,F3 != 1
Q4: 3.. = A5,A6: 3.. => A9 != 3
Q5: 2.. = D4,D5: 2.. => D2 != 2
Q8: 8.. = D7,D9: 8.. => D2 != 8
Q9: 8.. = I7,I9: 8.. => I5 != 8
Q5: 1.. = F5,F6: 1.. => F8 != 1
* UNSOLVED!

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

swordfish |:guess:| highlight 1

I3 != 1 => A1,G1,G4,B4,B3,A3: 1.. => A5,A6,G5,G6,G8 != 1 # swordfish

* DISABLE VALUE:: I3 != 1
I3: 2                 # naked single
* DISABLE VALUE:: A5 != 1
* DISABLE VALUE:: A6 != 1
A6: 3                 # naked single
* DISABLE VALUE:: G5 != 1
* DISABLE VALUE:: G6 != 1
* DISABLE VALUE:: G8 != 1

* AUTO ..
I3 = 2                # set value
G1: 1                 # naked single
A6 = 3                # set value
G6: 4                 # naked single
G6 = 4                # set value
F6: 1                 # naked single
B4: 1..               # hidden single
E8: 1..               # hidden single
G1 = 1                # set value
B4 = 1                # set value
B3: 5                 # naked single
F6 = 1                # set value
E8 = 1                # set value
A3: 1..               # hidden single
F8: 9..               # hidden single
E2: 9..               # hidden single
E2 = 9                # set value
F2: 8                 # naked single
F2 = 8                # set value
C2: 2                 # naked single
A3 = 1                # set value
B3 = 5                # set value
A1: 2                 # naked single
E3: 4                 # naked single
F3: 4                 # naked single
E3 = 4                # set value
F3 = 0 => CTR
* CTR!

=> I3 = 1
* FORCE VALUE:: I3 = 1
I3 = 1                # set value
G1: 2                 # naked single
B3: 5                 # naked single
A1: 1..               # hidden single
B4: 1..               # hidden single

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

* AUTO ..
A1 = 1                # set value
A6: 3                 # naked single
G1 = 2                # set value
E1: 5                 # naked single
B3 = 5                # set value
B4: 1                 # naked single
B4 = 1                # set value
G4: 8                 # naked single
G4 = 8                # set value
C4: 5                 # naked single
A6 = 3                # set value
A5: 8..               # hidden single
D4: 2..               # hidden single
C8: 2..               # hidden single
C2: 8..               # hidden single
E1 = 5                # set value
C2 = 8                # set value
A3: 2                 # naked single
F2: 9                 # naked single
F2 = 9                # set value
E2: 2                 # naked single
F8: 5                 # naked single
A3 = 2                # set value
A9: 5                 # naked single
E3: 4                 # naked single
E3 = 4                # set value
F3: 8                 # naked single
E9: 1                 # naked single
F3 = 8                # set value
C4 = 5                # set value
A5: 8                 # naked single
D4: 2                 # naked single
D4 = 2                # set value
A5 = 8                # set value
C8 = 2                # set value
C9: 3                 # naked single
F8 = 5                # set value
D8: 3                 # naked single
A9 = 5                # set value
C9 = 3                # set value
E9 = 1                # set value
E8: 9                 # naked single
H9: 2                 # naked single
H9 = 2                # set value
I9: 8                 # naked single
H5: 1                 # naked single
I9 = 8                # set value
I7: 3                 # naked single
D9: 4                 # naked single
D5: 5..               # hidden single
I5: 2..               # hidden single
D7: 8..               # hidden single
G8: 1..               # hidden single
E2 = 2                # set value
D5 = 5                # set value
H5 = 1                # set value
G6: 4                 # naked single
F5: 4                 # naked single
I5 = 2                # set value
G6 = 4                # set value
G5: 3                 # naked single
F6: 1                 # naked single
D7 = 8                # set value
I7 = 3                # set value
G8: 1                 # naked single
D8 = 3                # set value
E8 = 9                # set value
G8 = 1                # set value
D9 = 4                # set value
F5 = 4                # set value
G5 = 3                # set value
F6 = 1                # set value
* SOLVED!

|:step:| 02
--------------------------------------------------

Solution

position: 174653289638129754259748631415236897896574312327981465941862573782395146563417928 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 # A3: 2,8 => UNS
* DIS # A3: 1,5 => CTR => A3: 2,8
* INC # A1: 1,5 => UNS
* DIS # A3: 1,5 => CTR => A3: 2,8
* INC # A3: 2,8 => UNS
* DIS # E3: 2,5 => CTR => E3: 4
* PRF # E3: 4 => SOL
* DIS # A1: 2,5 => CTR => A1: 1
* PRF # A1: 1 => SOL
* INC # A1: 1,2 => UNS
* DIS # A1: 5 => CTR => A1: 1,2
* DIS # G4: 1,2 => CTR => G4: 8
* PRF # G4: 8 => SOL
* DIS # G5: 1,2 => CTR => G5: 3,4,8
* INC # G5: 3,4,8 => UNS
* PRF # G8: 1,2 => SOL
* DIS # G8: 3 => CTR => G8: 1,2
* PRF # A3: 1,2 => SOL
* INC # A3: 5,8 => UNS
* PRF # I5: 1,2 => SOL
* DIS # I5: 3 => CTR => I5: 1,2
* DIS # I9: 1,2 => CTR => I9: 3,8
* PRF # I9: 3,8 => SOL
* DIS # A5: 1,5 => CTR => A5: 3,8
* INC # A5: 3,8 => UNS
* INC # A5: 5,8 => UNS
* DIS # A5: 1,3 => CTR => A5: 5,8
* DIS # A5: 1,3 => CTR => A5: 5,8
* INC # A5: 5,8 => UNS
* DIS # G6: 1,3 => CTR => G6: 4
* INC # G6: 4 => UNS
* PRF # D5: 2,5 => SOL
* DIS # D5: 4 => CTR => D5: 2,5
* PRF # F5: 1,4 => SOL
* DIS # F5: 5 => CTR => F5: 1,4
* INC # G6: 1,4 => UNS
* DIS # G6: 3 => CTR => G6: 1,4
* DIS # G4: 1,2 => CTR => G4: 8
* PRF # G4: 8 => SOL
* DIS # G5: 1,2 => CTR => G5: 3,4,8
* INC # G5: 3,4,8 => UNS
* PRF # I5: 1,2 => SOL
* DIS # I5: 3 => CTR => I5: 1,2
* INC # C8: 2,5 => UNS
* DIS # C9: 2,5 => CTR => C9: 3
* INC # C9: 3 => UNS
* DIS # A1: 2,5 => CTR => A1: 1
* PRF # A1: 1 => SOL
* PRF # A3: 2,5 => SOL
* INC # A3: 1,8 => UNS
* DIS # D9: 3,8 => CTR => D9: 4,5
* PRF # D9: 4,5 => SOL
* DIS # D9: 3,5 => CTR => D9: 4,8
* INC # D9: 4,8 => UNS
* DIS # C8: 3,5 => CTR => C8: 2
* PRF # C8: 2 => SOL
* PRF # E8: 5,9 => SOL
* DIS # E8: 1 => CTR => E8: 5,9
* PRF # I9: 3,8 => SOL
* DIS # I9: 1,2 => CTR => I9: 3,8
* PRF # G8: 1,2 => SOL
* DIS # G8: 3 => CTR => G8: 1,2
* DIS # I9: 1,2 => CTR => I9: 3,8
* PRF # I9: 3,8 => SOL
* CNT  64 HDP CHAINS /  64 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* INC # A3: 2,8 => UNS
* DIS # A3: 1,5 => CTR => A3: 2,8
* DIS A3: 2,8 # E3: 2,5 => CTR => E3: 4
* PRF A3: 2,8 + E3: 4 => SOL
* STA A3: 2,8 + E3: 4
* CNT   4 HDP CHAINS /   3 HYP OPENED