Analysis of xx-top500-222-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: ....3..824.1..................4.65...8.....3....7........5..7..6.....4...3..2.... initial

Autosolve

position: ...1346824.18..3.........4....4.6578786.5..34.4.7832.6...54.7636..3..42..346278.. autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* DIS # A6: 5,9 => CTR => A6: 1
* PRF # A6: 1 => SOL
* PRF # A9: 5,9 => SOL
* DIS # A9: 1 => CTR => A9: 5,9
* DIS # F3: 2,9 => CTR => F3: 5
* DIS # I2: 5,9 => CTR => I2: 7
* DIS # I3: 5,9 => CTR => I3: 1,7
* DIS # F2: 2 => CTR => F2: 5,9
* DIS # H9: 5,9 => CTR => H9: 1
* PRF # H9: 1 => SOL
* PRF # I3: 1,9 => SOL
* DIS # I3: 5,7 => CTR => I3: 1,9
* DIS # A6: 5 => CTR => A6: 1,9
* DIS # A6: 5,9 => CTR => A6: 1
* PRF # A6: 1 => SOL
* DIS # F5: 1,9 => CTR => F5: 2
* PRF # F5: 2 => SOL
* PRF # F5: 2,9 => SOL
* DIS # F5: 1 => CTR => F5: 2,9
* DIS # F5: 1,9 => CTR => F5: 2
* PRF # F5: 2 => SOL
* DIS # A6: 5 => CTR => A6: 1,9
* DIS # H9: 5 => CTR => H9: 1,9
* PRF # C7: 9 => SOL
* PRF # A9: 5 => SOL
* PRF # F7: 8 => SOL
* PRF # C8: 8,9 => SOL
* PRF # F8: 1,9 => SOL
* PRF # I8: 5 => SOL
* CNT  29 HDP CHAINS /  50 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 # A6: 5,9 => CTR => A6: 1
* PRF A6: 1 => SOL
* STA A6: 1
* CNT   2 HDP CHAINS /   3 HYP OPENED

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

Details

Positions

....3..824.1..................4.65...8.....3....7........5..7..6.....4...3..2.... initial
...1346824.18..3.........4....4.6578786.5..34.4.7832.6...54.7636..3..42..346278.. autosolve
957134682421869357863275941392416578786952134145783296219548763678391425534627819 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (23)
A1: 5,9
B1: 5,7
B2: 2,6
A3: 3,8
B3: 2,6
C3: 3,8
E2: 6,7
D3: 2,9
E3: 6,7
H2: 5,9
G3: 1,9
A4: 2,3
B4: 1,9
C4: 2,3
C6: 5,9
E4: 1,9
D5: 2,9
G5: 1,9
H6: 1,9
A7: 2,8
B7: 1,9
B8: 5,7
E8: 1,9

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
G3,I3: 1.. / G3 = 1  =>  0 pairs (X) / I3 = 1  =>  0 pairs (_)
B4,A6: 1.. / B4 = 1  =>  0 pairs (X) / A6 = 1  =>  0 pairs (_)
E4,F5: 1.. / E4 = 1  =>  0 pairs (*) / F5 = 1  =>  0 pairs (X)
G5,H6: 1.. / G5 = 1  =>  0 pairs (*) / H6 = 1  =>  0 pairs (X)
B7,A9: 1.. / B7 = 1  =>  0 pairs (*) / A9 = 1  =>  0 pairs (X)
B4,E4: 1.. / B4 = 1  =>  0 pairs (X) / E4 = 1  =>  0 pairs (_)
F5,G5: 1.. / F5 = 1  =>  0 pairs (X) / G5 = 1  =>  0 pairs (_)
A6,H6: 1.. / A6 = 1  =>  0 pairs (*) / H6 = 1  =>  0 pairs (X)
B7,F7: 1.. / B7 = 1  =>  0 pairs (*) / F7 = 1  =>  0 pairs (X)
A6,A9: 1.. / A6 = 1  =>  0 pairs (*) / A9 = 1  =>  0 pairs (X)
B4,B7: 1.. / B4 = 1  =>  0 pairs (X) / B7 = 1  =>  0 pairs (_)
E4,E8: 1.. / E4 = 1  =>  0 pairs (*) / E8 = 1  =>  0 pairs (X)
G3,G5: 1.. / G3 = 1  =>  0 pairs (X) / G5 = 1  =>  0 pairs (_)
H6,H9: 1.. / H6 = 1  =>  0 pairs (X) / H9 = 1  =>  0 pairs (_)
B2,B3: 2.. / B2 = 2  => 20 pairs (_) / B3 = 2  =>  0 pairs (X)
A4,C4: 2.. / A4 = 2  => 19 pairs (_) / C4 = 2  => 19 pairs (_)
D5,F5: 2.. / D5 = 2  =>  0 pairs (X) / F5 = 2  =>  0 pairs (_)
A7,C7: 2.. / A7 = 2  => 19 pairs (_) / C7 = 2  => 19 pairs (_)
B2,F2: 2.. / B2 = 2  => 20 pairs (_) / F2 = 2  =>  0 pairs (X)
A4,A7: 2.. / A4 = 2  => 19 pairs (_) / A7 = 2  => 19 pairs (_)
C4,C7: 2.. / C4 = 2  => 19 pairs (_) / C7 = 2  => 19 pairs (_)
D3,D5: 2.. / D3 = 2  =>  0 pairs (*) / D5 = 2  =>  0 pairs (X)
A3,C3: 3.. / A3 = 3  => 19 pairs (_) / C3 = 3  => 19 pairs (_)
A4,C4: 3.. / A4 = 3  => 19 pairs (_) / C4 = 3  => 19 pairs (_)
A3,A4: 3.. / A3 = 3  => 19 pairs (_) / A4 = 3  => 19 pairs (_)
C3,C4: 3.. / C3 = 3  => 19 pairs (_) / C4 = 3  => 19 pairs (_)
F2,F3: 5.. / F2 = 5  =>  0 pairs (X) / F3 = 5  => 24 pairs (_)
A6,C6: 5.. / A6 = 5  =>  0 pairs (X) / C6 = 5  => 24 pairs (_)
F3,I3: 5.. / F3 = 5  => 24 pairs (_) / I3 = 5  =>  0 pairs (X)
B1,B8: 5.. / B1 = 5  => 23 pairs (_) / B8 = 5  => 26 pairs (_)
H2,H9: 5.. / H2 = 5  => 25 pairs (_) / H9 = 5  =>  0 pairs (X)
B2,B3: 6.. / B2 = 6  =>  0 pairs (X) / B3 = 6  => 20 pairs (_)
E2,E3: 6.. / E2 = 6  => 20 pairs (_) / E3 = 6  =>  0 pairs (X)
B2,E2: 6.. / B2 = 6  =>  0 pairs (X) / E2 = 6  => 20 pairs (_)
B3,E3: 6.. / B3 = 6  => 20 pairs (_) / E3 = 6  =>  0 pairs (X)
B1,C1: 7.. / B1 = 7  => 26 pairs (_) / C1 = 7  => 23 pairs (_)
E2,E3: 7.. / E2 = 7  =>  0 pairs (X) / E3 = 7  => 20 pairs (_)
I2,I3: 7.. / I2 = 7  => 20 pairs (_) / I3 = 7  =>  0 pairs (X)
B8,C8: 7.. / B8 = 7  => 23 pairs (_) / C8 = 7  => 26 pairs (_)
E2,I2: 7.. / E2 = 7  =>  0 pairs (X) / I2 = 7  => 20 pairs (_)
E3,I3: 7.. / E3 = 7  => 20 pairs (_) / I3 = 7  =>  0 pairs (X)
B1,B8: 7.. / B1 = 7  => 26 pairs (_) / B8 = 7  => 23 pairs (_)
C1,C8: 7.. / C1 = 7  => 23 pairs (_) / C8 = 7  => 26 pairs (_)
A3,C3: 8.. / A3 = 8  => 19 pairs (_) / C3 = 8  => 19 pairs (_)
F7,F8: 8.. / F7 = 8  =>  0 pairs (*) / F8 = 8  =>  0 pairs (X)
C8,F8: 8.. / C8 = 8  =>  0 pairs (*) / F8 = 8  =>  0 pairs (X)
A3,A7: 8.. / A3 = 8  => 19 pairs (_) / A7 = 8  => 19 pairs (_)
A1,C1: 9.. / A1 = 9  => 26 pairs (_) / C1 = 9  => 24 pairs (_)
G5,H6: 9.. / G5 = 9  =>  0 pairs (X) / H6 = 9  =>  0 pairs (_)
B4,E4: 9.. / B4 = 9  =>  0 pairs (*) / E4 = 9  =>  0 pairs (X)
B4,B7: 9.. / B4 = 9  =>  0 pairs (*) / B7 = 9  =>  0 pairs (X)
D3,D5: 9.. / D3 = 9  =>  0 pairs (X) / D5 = 9  =>  0 pairs (_)
E4,E8: 9.. / E4 = 9  =>  0 pairs (X) / E8 = 9  =>  0 pairs (_)
G3,G5: 9.. / G3 = 9  =>  0 pairs (*) / G5 = 9  =>  0 pairs (X)
* DURATION: 0:02:02.018847  START: 10:22:12.342715  END: 10:24:14.361562 2017-05-04
* CP COUNT: (54)
* SOLUTION FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A1,A3,A4,A7,B1,B2,B3,B4,B7,B8,C3,C4,C6,D3,D5,E2,E3,E4,E8,G3,G5,H2,H6)
* ...1346824.18..3.........4....4.6578786.5..34.4.7832.6...54.7636..3..42..346278..
* PAIR A1: 5,9 BLK 1
C1: 5,9,7                                # reduction candidate for 5,9
C1: 5,9                                  # 26 pairs
C1: 7                                    # 23 pairs
* PAIR A1: 5,9 COL A
A6: 5,9,1                                # reduction candidate for 5,9
A6: 5,9 => CTR
* ...1346824.18..3.........4..1.496578786251934.4.783216.9.5487636.8319425.346278..
A6: 1 => SOLVED
* 957134682421869357863275941392416578786952134145783296219548763678391425534627819
A9: 5,9,1                                # reduction candidate for 5,9
A9: 5,9 => SOLVED
* 957134682421869357863275941392416578786952134145783296219548763678391425534627819
A9: 1 => CTR
* ...1346824.18..3.........4..1.496578786251934.4.783216.9.5487636.831.42.1346278..
* PAIR B1: 5,7 BLK 1
C1: 5,7,9                                # reduction candidate for 5,7
C1: 5,7                                  # 26 pairs
C1: 9                                    # 24 pairs
* PAIR D3: 2,9 BLK 2
F2: 2,9,5                                # reduction candidate for 2,9
F2: 2,9                                  # 24 pairs
F3: 2,9,5                                # reduction candidate for 2,9
F3: 2,9 => CTR
* ...1346824.18.5397....7.145...4.6578786.51934.4.783216.1.54.7636..31.429934627851
F3: 5                                    # 24 pairs
* PAIR H2: 5,9 BLK 3
I2: 5,9,7                                # reduction candidate for 5,9
I2: 5,9 => CTR
* ...1346824618723...2.965147...4.6578786251934.4.783216.1.54.7636..31.42..346278.1
I2: 7                                    # 20 pairs
I3: 5,9,1,7                              # reduction candidate for 5,9
I3: 5,9 => CTR
* ...1346824.18..3.7....7.14....4.6578786.51934.4.783216.1.54.7636..31.42..346278.1
I3: 1,7                                  # 25 pairs
* PAIR H2: 5,9 ROW 2
F2: 5,9,2                                # reduction candidate for 5,9
F2: 2 => CTR
* ...1346824.18.23...2.965147...4.6578786251934.4.783216.1.54.7636..31.42..346278.1
F2: 5,9                                  # 20 pairs
* PAIR H2: 5,9 COL H
H9: 5,9,1                                # reduction candidate for 5,9
H9: 5,9 => CTR
* ...1346824.18..3........14..1.496578786251934.4.783216.9.5487636.831.42.1346278..
H9: 1 => SOLVED
* 957134682421869357863275941392416578786952134145783296219548763678391425534627819
* PAIR G3: 1,9 BLK 3
I3: 1,9,5,7                              # reduction candidate for 1,9
I3: 1,9 => SOLVED
* 957134682421869357863275941392416578786952134145783296219548763678391425534627819
I3: 5,7 => CTR
* ...1346824.18..3........14....4.6578786.51934.4.783216.1.54.7636..31.42..346278.1
* PAIR B4: 1,9 BLK 4
A6: 1,9,5                                # reduction candidate for 1,9
A6: 5 => CTR
* ...1346824.18..3.........4..1.496578786251934549783216.9.5487636.831.42..346278..
A6: 1,9                                  # 24 pairs
* PAIR C6: 5,9 BLK 4
A6: 5,9,1                                # reduction candidate for 5,9
A6: 5,9 => CTR
* ...1346824.18..3.........4..1.496578786251934.4.783216.9.5487636.8319425.346278..
A6: 1 => SOLVED
* 957134682421869357863275941392416578786952134145783296219548763678391425534627819
* PAIR C6: 5,9 COL C
C1: 5,9,7                                # reduction candidate for 5,9
C1: 5,9                                  # 26 pairs
C8: 5,9,7,8                              # reduction candidate for 5,9
C8: 5,9                                  # 26 pairs
* PAIR E4: 1,9 BLK 5
F5: 1,9,2                                # reduction candidate for 1,9
F5: 1,9 => CTR
* ...1346824.18..3.....9..14....4.6578786251934.4.783216.1.54.7636..31.42..346278.1
F5: 2 => SOLVED
* 957134682421869357863275941392416578786952134145783296219548763678391425534627819
* PAIR D5: 2,9 BLK 5
F5: 2,9,1                                # reduction candidate for 2,9
F5: 2,9 => SOLVED
* 957134682421869357863275941392416578786952134145783296219548763678391425534627819
F5: 1 => CTR
* ...1346824.18..3.........4....4.6578786251934.4.783216.1.54.7636..31.42..346278.1
* PAIR G5: 1,9 ROW 5
F5: 1,9,2                                # reduction candidate for 1,9
F5: 1,9 => CTR
* ...1346824.18..3.....9..14....4.6578786251934.4.783216.1.54.7636..31.42..346278.1
F5: 2 => SOLVED
* 957134682421869357863275941392416578786952134145783296219548763678391425534627819
* PAIR H6: 1,9 ROW 6
A6: 1,9,5                                # reduction candidate for 1,9
A6: 5 => CTR
* ...1346824.18..3.........4..1.496578786251934549783216.9.5487636.831.42..346278..
A6: 1,9                                  # 24 pairs
* PAIR H6: 1,9 COL H
H9: 1,9,5                                # reduction candidate for 1,9
H9: 5 => CTR
* ...1346824.18..39.......14..1.496578786251934.4.783216.9.5487636.831.42.134627859
H9: 1,9                                  # 25 pairs
* PAIR A7: 2,8 BLK 7
C7: 2,8,9                                # reduction candidate for 2,8
C7: 9 => SOLVED
* 957134682421869357863275941392416578786952134145783296219548763678391425534627819
C7: 2,8                                  # 25 pairs
* PAIR B7: 1,9 BLK 7
A9: 1,9,5                                # reduction candidate for 1,9
A9: 5 => SOLVED
* 957134682421869357863275941392416578786952134145783296219548763678391425534627819
A9: 1,9                                  # 28 pairs
* PAIR B7: 1,9 ROW 7
F7: 1,9,8                                # reduction candidate for 1,9
F7: 8 => SOLVED
* 957134682421869357863275941392416578786952134145783296219548763678391425534627819
F7: 1,9                                  # 25 pairs
* PAIR B8: 5,7 BLK 7
C8: 5,7,8,9                              # reduction candidate for 5,7
C8: 8,9 => SOLVED
* 957134682421869357863275941392416578786952134145783296219548763678391425534627819
C8: 5,7                                  # 28 pairs
* PAIR E8: 1,9 BLK 8
F7: 1,9,8                                # reduction candidate for 1,9
F7: 1,9                                  # 25 pairs
F8: 1,9,8                                # reduction candidate for 1,9
F8: 1,9 => SOLVED
* 957134682421869357863275941392416578786952134145783296219548763678391425534627819
F8: 8                                    # 25 pairs
* PAIR E8: 1,9 ROW 8
I8: 1,9,5                                # reduction candidate for 1,9
I8: 5 => SOLVED
* 957134682421869357863275941392416578786952134145783296219548763678391425534627819
I8: 1,9                                  # 28 pairs
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-222-base-pr-000.dot
* REASONING
* DIS # A6: 5,9 => CTR => A6: 1
* PRF # A6: 1 => SOL
* PRF # A9: 5,9 => SOL
* DIS # A9: 1 => CTR => A9: 5,9
* DIS # F3: 2,9 => CTR => F3: 5
* DIS # I2: 5,9 => CTR => I2: 7
* DIS # I3: 5,9 => CTR => I3: 1,7
* DIS # F2: 2 => CTR => F2: 5,9
* DIS # H9: 5,9 => CTR => H9: 1
* PRF # H9: 1 => SOL
* PRF # I3: 1,9 => SOL
* DIS # I3: 5,7 => CTR => I3: 1,9
* DIS # A6: 5 => CTR => A6: 1,9
* DIS # A6: 5,9 => CTR => A6: 1
* PRF # A6: 1 => SOL
* DIS # F5: 1,9 => CTR => F5: 2
* PRF # F5: 2 => SOL
* PRF # F5: 2,9 => SOL
* DIS # F5: 1 => CTR => F5: 2,9
* DIS # F5: 1,9 => CTR => F5: 2
* PRF # F5: 2 => SOL
* DIS # A6: 5 => CTR => A6: 1,9
* DIS # H9: 5 => CTR => H9: 1,9
* PRF # C7: 9 => SOL
* PRF # A9: 5 => SOL
* PRF # F7: 8 => SOL
* PRF # C8: 8,9 => SOL
* PRF # F8: 1,9 => SOL
* PRF # I8: 5 => SOL
* CNT  29 HDP CHAINS /  50 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A1,A3,A4,A7,B1,B2,B3,B4,B7,B8,C3,C4,C6,D3,D5,E2,E3,E4,E8,G3,G5,H2,H6)
* ...1346824.18..3.........4....4.6578786.5..34.4.7832.6...54.7636..3..42..346278..
* PAIR A1: 5,9 BLK 1
C1: 5,9,7                                # reduction candidate for 5,9
C1: 5,9                                  # 26 pairs
C1: 7                                    # 23 pairs
* PAIR A1: 5,9 COL A
A6: 5,9,1                                # reduction candidate for 5,9
A6: 5,9 => CTR
* ...1346824.18..3.........4..1.496578786251934.4.783216.9.5487636.8319425.346278..
A6: 1 => SOLVED
* 957134682421869357863275941392416578786952134145783296219548763678391425534627819
* DURATION: 0:00:04.433823  START: 10:25:23.353743  END: 10:25:27.787566 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-222-base-pr-001.dot
* REASONING
* DIS # A6: 5,9 => CTR => A6: 1
* PRF A6: 1 => SOL
* STA A6: 1
* CNT   2 HDP CHAINS /   3 HYP OPENED

Header Info

Top 500 Minimum 17 222

solution: 957134682421869357863275941392416578786952134145783296219548763678391425534627819
info: 1991     FNBTHWX  S8.f     3786

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

Solution

position: 957134682421869357863275941392416578786952134145783296219548763678391425534627819 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 # C1: 5,9 => UNS
* INC # C1: 7 => UNS
* DIS # A6: 5,9 => CTR => A6: 1
* PRF # A6: 1 => SOL
* PRF # A9: 5,9 => SOL
* DIS # A9: 1 => CTR => A9: 5,9
* INC # C1: 5,7 => UNS
* INC # C1: 9 => UNS
* INC # F2: 2,9 => UNS
* DIS # F3: 2,9 => CTR => F3: 5
* INC # F3: 5 => UNS
* DIS # I2: 5,9 => CTR => I2: 7
* INC # I2: 7 => UNS
* DIS # I3: 5,9 => CTR => I3: 1,7
* INC # I3: 1,7 => UNS
* INC # F2: 5,9 => UNS
* DIS # F2: 2 => CTR => F2: 5,9
* DIS # H9: 5,9 => CTR => H9: 1
* PRF # H9: 1 => SOL
* PRF # I3: 1,9 => SOL
* DIS # I3: 5,7 => CTR => I3: 1,9
* INC # A6: 1,9 => UNS
* DIS # A6: 5 => CTR => A6: 1,9
* DIS # A6: 5,9 => CTR => A6: 1
* PRF # A6: 1 => SOL
* INC # C1: 5,9 => UNS
* INC # C8: 5,9 => UNS
* DIS # F5: 1,9 => CTR => F5: 2
* PRF # F5: 2 => SOL
* PRF # F5: 2,9 => SOL
* DIS # F5: 1 => CTR => F5: 2,9
* DIS # F5: 1,9 => CTR => F5: 2
* PRF # F5: 2 => SOL
* INC # A6: 1,9 => UNS
* DIS # A6: 5 => CTR => A6: 1,9
* INC # H9: 1,9 => UNS
* DIS # H9: 5 => CTR => H9: 1,9
* INC # C7: 2,8 => UNS
* PRF # C7: 9 => SOL
* INC # A9: 1,9 => UNS
* PRF # A9: 5 => SOL
* INC # F7: 1,9 => UNS
* PRF # F7: 8 => SOL
* INC # C8: 5,7 => UNS
* PRF # C8: 8,9 => SOL
* INC # F7: 1,9 => UNS
* PRF # F8: 1,9 => SOL
* INC # F8: 8 => UNS
* INC # I8: 1,9 => UNS
* PRF # I8: 5 => SOL
* CNT  50 HDP CHAINS /  50 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* INC # C1: 5,9 => UNS
* INC # C1: 7 => UNS
* DIS # A6: 5,9 => CTR => A6: 1
* PRF A6: 1 => SOL
* STA A6: 1
* CNT   4 HDP CHAINS /   3 HYP OPENED