Analysis of xx-top500-363-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: 9.....68.4...7..........2...8.....17...42..............7.8.1......9..4..3........ initial

Autosolve

position: 9.715.68.4.8.7.1..1...8.27.284.9..1771.4289...9.71.842.79841.2.8.29374.1341.6.798 autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* DIS # B2: 6 => CTR => B2: 2,3
* DIS # F1: 4 => CTR => F1: 2,3
* DIS # B3: 3 => CTR => B3: 5,6
* PRF # C6: 5,6 => SOL
* DIS # C6: 3 => CTR => C6: 5,6
* PRF # D2: 3,6 => SOL
* DIS # F2: 3,6 => CTR => F2: 2,9
* PRF # B3: 3,6 => SOL
* DIS # B3: 5 => CTR => B3: 3,6
* PRF # D4: 5 => SOL
* PRF # F1: 2 => SOL
* DIS # I2: 9 => CTR => I2: 3,5
* PRF # H5: 3,5 => SOL
* DIS # H5: 6 => CTR => H5: 3,5
* DIS # C6: 3,5 => CTR => C6: 6
* PRF # C6: 6 => SOL
* PRF # H5: 3,5 => SOL
* DIS # H5: 6 => CTR => H5: 3,5
* DIS # I5: 3,5 => CTR => I5: 6
* PRF # I5: 6 => SOL
* PRF # C6: 5,6 => SOL
* DIS # C6: 3 => CTR => C6: 5,6
* DIS # F4: 3,5 => CTR => F4: 6
* DIS # C6: 3,5 => CTR => C6: 6
* PRF # C6: 6 => SOL
* PRF # H5: 3,5 => SOL
* DIS # H5: 6 => CTR => H5: 3,5
* DIS # I5: 3,5 => CTR => I5: 6
* PRF # I5: 6 => SOL
* DIS # F4: 3,5 => CTR => F4: 6
* DIS # I7: 5,6 => CTR => I7: 3
* PRF # I7: 3 => SOL
* DIS # B3: 3 => CTR => B3: 5,6
* PRF # I7: 3,5 => SOL
* DIS # I7: 6 => CTR => I7: 3,5
* DIS # I7: 5,6 => CTR => I7: 3
* PRF # I7: 3 => SOL
* DIS # H5: 3 => CTR => H5: 5,6
* CNT  38 HDP CHAINS /  52 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 # B2: 6 => CTR => B2: 2,3
* PRF B2: 2,3 # C6: 5,6 => SOL
* STA B2: 2,3 + C6: 5,6
* CNT   2 HDP CHAINS /   3 HYP OPENED

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

Details

Positions

9.....68.4...7..........2...8.....17...42..............7.8.1......9..4..3........ initial
9.715.68.4.8.7.1..1...8.27.284.9..1771.4289...9.71.842.79841.2.8.29374.1341.6.798 autosolve
937152684428679135165384279284596317713428956596713842679841523852937461341265798 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (17)
B1: 2,3
C3: 5,6
D3: 3,6
F3: 4,9
I1: 3,4
H2: 3,5
I3: 4,9
C5: 3,5
A6: 5,6
F6: 3,5
G4: 3,5
A7: 5,6
B8: 5,6
D9: 2,5
F9: 2,5
G7: 3,5
H8: 5,6

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
B1,B2: 2.. / B1 = 2  => 18 pairs (_) / B2 = 2  =>  0 pairs (*)
D9,F9: 2.. / D9 = 2  =>  0 pairs (*) / F9 = 2  =>  0 pairs (X)
B1,F1: 2.. / B1 = 2  => 18 pairs (_) / F1 = 2  =>  0 pairs (*)
D2,D9: 2.. / D2 = 2  => 17 pairs (_) / D9 = 2  =>  0 pairs (*)
C5,C6: 3.. / C5 = 3  =>  0 pairs (*) / C6 = 3  =>  0 pairs (X)
G7,I7: 3.. / G7 = 3  =>  0 pairs (X) / I7 = 3  =>  0 pairs (_)
B3,D3: 3.. / B3 = 3  =>  0 pairs (X) / D3 = 3  => 21 pairs (_)
C6,F6: 3.. / C6 = 3  =>  0 pairs (X) / F6 = 3  =>  0 pairs (_)
G4,G7: 3.. / G4 = 3  =>  0 pairs (*) / G7 = 3  =>  0 pairs (X)
H2,H5: 3.. / H2 = 3  => 20 pairs (_) / H5 = 3  =>  0 pairs (X)
F1,F3: 4.. / F1 = 4  =>  0 pairs (X) / F3 = 4  => 19 pairs (_)
I1,I3: 4.. / I1 = 4  => 19 pairs (_) / I3 = 4  =>  0 pairs (X)
F1,I1: 4.. / F1 = 4  =>  0 pairs (X) / I1 = 4  => 19 pairs (_)
F3,I3: 4.. / F3 = 4  => 19 pairs (_) / I3 = 4  =>  0 pairs (X)
B3,C3: 5.. / B3 = 5  =>  0 pairs (X) / C3 = 5  =>  0 pairs (_)
H2,I2: 5.. / H2 = 5  =>  0 pairs (X) / I2 = 5  => 20 pairs (_)
A7,B8: 5.. / A7 = 5  =>  0 pairs (X) / B8 = 5  =>  0 pairs (_)
D9,F9: 5.. / D9 = 5  => 17 pairs (_) / F9 = 5  =>  0 pairs (*)
B8,H8: 5.. / B8 = 5  =>  0 pairs (*) / H8 = 5  =>  0 pairs (X)
A6,A7: 5.. / A6 = 5  =>  0 pairs (*) / A7 = 5  =>  0 pairs (X)
B3,B8: 5.. / B3 = 5  =>  0 pairs (X) / B8 = 5  =>  0 pairs (_)
D4,D9: 5.. / D4 = 5  =>  0 pairs (*) / D9 = 5  =>  0 pairs (X)
G4,G7: 5.. / G4 = 5  =>  0 pairs (X) / G7 = 5  =>  0 pairs (_)
A6,C6: 6.. / A6 = 6  =>  0 pairs (X) / C6 = 6  =>  0 pairs (_)
D4,F4: 6.. / D4 = 6  =>  0 pairs (X) / F4 = 6  => 18 pairs (_)
H5,I5: 6.. / H5 = 6  =>  0 pairs (X) / I5 = 6  =>  0 pairs (_)
A7,B8: 6.. / A7 = 6  =>  0 pairs (*) / B8 = 6  =>  0 pairs (X)
I7,H8: 6.. / I7 = 6  =>  0 pairs (X) / H8 = 6  =>  0 pairs (_)
A7,I7: 6.. / A7 = 6  =>  0 pairs (*) / I7 = 6  =>  0 pairs (X)
B8,H8: 6.. / B8 = 6  =>  0 pairs (X) / H8 = 6  =>  0 pairs (_)
A6,A7: 6.. / A6 = 6  =>  0 pairs (X) / A7 = 6  =>  0 pairs (_)
C3,C6: 6.. / C3 = 6  =>  0 pairs (X) / C6 = 6  =>  0 pairs (_)
F2,F4: 6.. / F2 = 6  =>  0 pairs (X) / F4 = 6  => 18 pairs (_)
H5,H8: 6.. / H5 = 6  =>  0 pairs (X) / H8 = 6  =>  0 pairs (_)
I5,I7: 6.. / I5 = 6  =>  0 pairs (*) / I7 = 6  =>  0 pairs (X)
F2,F3: 9.. / F2 = 9  => 19 pairs (_) / F3 = 9  =>  0 pairs (X)
I2,I3: 9.. / I2 = 9  =>  0 pairs (X) / I3 = 9  => 19 pairs (_)
F2,I2: 9.. / F2 = 9  => 19 pairs (_) / I2 = 9  =>  0 pairs (X)
F3,I3: 9.. / F3 = 9  =>  0 pairs (X) / I3 = 9  => 19 pairs (_)
* DURATION: 0:01:14.049336  START: 15:12:32.282468  END: 15:13:46.331804 2017-05-04
* CP COUNT: (39)
* SOLUTION FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A6,A7,B1,B8,C3,C5,D3,D9,F3,F6,F9,G4,G7,H2,H8,I1,I3)
* 9.715.68.4.8.7.1..1...8.27.284.9..1771.4289...9.71.842.79841.2.8.29374.1341.6.798
* PAIR B1: 2,3 BLK 1
B2: 2,3,6                                # reduction candidate for 2,3
B2: 6 => CTR
* 92715468346837215.13568.27.284.96.177134289..596713842679841.2.852937461341.65798
B2: 2,3                                  # 21 pairs
* PAIR B1: 2,3 ROW 1
F1: 2,3,4                                # reduction candidate for 2,3
F1: 4 => CTR
* 9271546834.8.7.1591...89274284.9..1771.428936.93715842.79841.2.8.29374.1341.6.798
F1: 2,3                                  # 19 pairs
* PAIR C3: 5,6 BLK 1
B3: 5,6,3                                # reduction candidate for 5,6
B3: 3 => CTR
* 92715468346837215.13568.27.284.96.177134289..596713842679841.2.852937461341.65798
B3: 5,6                                  # 21 pairs
* PAIR C3: 5,6 COL C
C6: 5,6,3                                # reduction candidate for 5,6
C6: 5,6 => SOLVED
* 937152684428679135165384279284596317713428956596713842679841523852937461341265798
C6: 3 => CTR
* 9271546834.8.7.1..1.638.27.284.9..177154289..693715842579841326862937451341562798
* PAIR D3: 3,6 BLK 2
D2: 3,6,2                                # reduction candidate for 3,6
D2: 3,6 => SOLVED
* 937152684428679135165384279284596317713428956596713842679841523852937461341265798
D2: 2                                    # 17 pairs
F2: 3,6,2,9                              # reduction candidate for 3,6
F2: 3,6 => CTR
* 9.71546834.827.1591...89274284.9..1771.428936.93715842.79841.2.8.29374.1341.6.798
F2: 2,9                                  # 19 pairs
* PAIR D3: 3,6 ROW 3
B3: 3,6,5                                # reduction candidate for 3,6
B3: 3,6 => SOLVED
* 937152684428679135165384279284596317713428956596713842679841523852937461341265798
B3: 5 => CTR
* 9.715.68.4.8.7.13515638.279284.93517715428963693715842579841326862937451341.6.798
* PAIR D3: 3,6 COL D
D4: 3,6,5                                # reduction candidate for 3,6
D4: 5 => SOLVED
* 937152684428679135165384279284596317713428956596713842679841523852937461341265798
D4: 3,6                                  # 17 pairs
* PAIR I1: 3,4 ROW 1
F1: 3,4,2                                # reduction candidate for 3,4
F1: 2 => SOLVED
* 937152684428679135165384279284596317713428956596713842679841523852937461341265798
F1: 3,4                                  # 18 pairs
* PAIR H2: 3,5 BLK 3
I2: 3,5,9                                # reduction candidate for 3,5
I2: 9 => CTR
* 9.715.68.4.8.7.1591...89274284.9..1771.428936.93715842.79841.2.8.29374.1341.6.798
I2: 3,5                                  # 19 pairs
* PAIR H2: 3,5 COL H
H5: 3,5,6                                # reduction candidate for 3,5
H5: 3,5 => SOLVED
* 937152684428679135165384279284596317713428956596713842679841523852937461341265798
H5: 6 => CTR
* 92715.68.4.8.7.1351...8.279284.9.517715428963693715842579841326862937451341562798
* PAIR C5: 3,5 BLK 4
C6: 3,5,6                                # reduction candidate for 3,5
C6: 3,5 => CTR
* 9.715.68.4.8.7.13515638.279284.93517715428963693715842579841326862937451341.6.798
C6: 6 => SOLVED
* 937152684428679135165384279284596317713428956596713842679841523852937461341265798
* PAIR C5: 3,5 ROW 5
H5: 3,5,6                                # reduction candidate for 3,5
H5: 3,5 => SOLVED
* 937152684428679135165384279284596317713428956596713842679841523852937461341265798
H5: 6 => CTR
* 92715.68.4.8.7.1351...8.279284.9.517715428963693715842579841326862937451341562798
I5: 3,5,6                                # reduction candidate for 3,5
I5: 3,5 => CTR
* 9.715.68.4.8.7.13515638.279284.9.517715428963693715842579841326862937451341562798
I5: 6 => SOLVED
* 937152684428679135165384279284596317713428956596713842679841523852937461341265798
* PAIR A6: 5,6 BLK 4
C6: 5,6,3                                # reduction candidate for 5,6
C6: 5,6 => SOLVED
* 937152684428679135165384279284596317713428956596713842679841523852937461341265798
C6: 3 => CTR
* 9271546834.8.7.1..1.638.27.284.9..177154289..693715842579841326862937451341562798
* PAIR F6: 3,5 BLK 5
D4: 3,5,6                                # reduction candidate for 3,5
D4: 3,5                                  # 18 pairs
F4: 3,5,6                                # reduction candidate for 3,5
F4: 3,5 => CTR
* 9271546834382761591..38927428469..1771.428936.93715842.79841.2.8.29374.1341562798
F4: 6                                    # 18 pairs
* PAIR F6: 3,5 ROW 6
C6: 3,5,6                                # reduction candidate for 3,5
C6: 3,5 => CTR
* 9.715.68.4.8.7.13515638.279284.93517715428963693715842579841326862937451341.6.798
C6: 6 => SOLVED
* 937152684428679135165384279284596317713428956596713842679841523852937461341265798
* PAIR G4: 3,5 BLK 6
H5: 3,5,6                                # reduction candidate for 3,5
H5: 3,5 => SOLVED
* 937152684428679135165384279284596317713428956596713842679841523852937461341265798
H5: 6 => CTR
* 92715.68.4.8.7.1351...8.279284.9.517715428963693715842579841326862937451341562798
I5: 3,5,6                                # reduction candidate for 3,5
I5: 3,5 => CTR
* 9.715.68.4.8.7.13515638.279284.9.517715428963693715842579841326862937451341562798
I5: 6 => SOLVED
* 937152684428679135165384279284596317713428956596713842679841523852937461341265798
* PAIR G4: 3,5 ROW 4
D4: 3,5,6                                # reduction candidate for 3,5
D4: 3,5                                  # 18 pairs
F4: 3,5,6                                # reduction candidate for 3,5
F4: 3,5 => CTR
* 9271546834382761591..38927428469..1771.428936.93715842.79841.2.8.29374.1341562798
F4: 6                                    # 18 pairs
* PAIR A7: 5,6 ROW 7
I7: 5,6,3                                # reduction candidate for 5,6
I7: 5,6 => CTR
* 92715.68.438.7.1..1...8.27.284.9.5177154289..693715842579841326862937451341562798
I7: 3 => SOLVED
* 937152684428679135165384279284596317713428956596713842679841523852937461341265798
* PAIR B8: 5,6 COL B
B3: 5,6,3                                # reduction candidate for 5,6
B3: 3 => CTR
* 92715468346837215.13568.27.284.96.177134289..596713842679841.2.852937461341.65798
B3: 5,6                                  # 21 pairs
* PAIR G7: 3,5 BLK 9
I7: 3,5,6                                # reduction candidate for 3,5
I7: 3,5 => SOLVED
* 937152684428679135165384279284596317713428956596713842679841523852937461341265798
I7: 6 => CTR
* 9.715.68.4.8.7.13515638.279284.93517715428963693715842.79841326862937451341.6.798
* PAIR H8: 5,6 BLK 9
I7: 5,6,3                                # reduction candidate for 5,6
I7: 5,6 => CTR
* 92715.68.438.7.1..1...8.27.284.9.5177154289..693715842579841326862937451341562798
I7: 3 => SOLVED
* 937152684428679135165384279284596317713428956596713842679841523852937461341265798
* PAIR H8: 5,6 COL H
H5: 5,6,3                                # reduction candidate for 5,6
H5: 3 => CTR
* 9.715.68.4.8.7.1..1...8.27.284.9..1771.428936.93715842.79841.2.8.29374.1341.6.798
H5: 5,6                                  # 20 pairs
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-363-base-pr-000.dot
* REASONING
* DIS # B2: 6 => CTR => B2: 2,3
* DIS # F1: 4 => CTR => F1: 2,3
* DIS # B3: 3 => CTR => B3: 5,6
* PRF # C6: 5,6 => SOL
* DIS # C6: 3 => CTR => C6: 5,6
* PRF # D2: 3,6 => SOL
* DIS # F2: 3,6 => CTR => F2: 2,9
* PRF # B3: 3,6 => SOL
* DIS # B3: 5 => CTR => B3: 3,6
* PRF # D4: 5 => SOL
* PRF # F1: 2 => SOL
* DIS # I2: 9 => CTR => I2: 3,5
* PRF # H5: 3,5 => SOL
* DIS # H5: 6 => CTR => H5: 3,5
* DIS # C6: 3,5 => CTR => C6: 6
* PRF # C6: 6 => SOL
* PRF # H5: 3,5 => SOL
* DIS # H5: 6 => CTR => H5: 3,5
* DIS # I5: 3,5 => CTR => I5: 6
* PRF # I5: 6 => SOL
* PRF # C6: 5,6 => SOL
* DIS # C6: 3 => CTR => C6: 5,6
* DIS # F4: 3,5 => CTR => F4: 6
* DIS # C6: 3,5 => CTR => C6: 6
* PRF # C6: 6 => SOL
* PRF # H5: 3,5 => SOL
* DIS # H5: 6 => CTR => H5: 3,5
* DIS # I5: 3,5 => CTR => I5: 6
* PRF # I5: 6 => SOL
* DIS # F4: 3,5 => CTR => F4: 6
* DIS # I7: 5,6 => CTR => I7: 3
* PRF # I7: 3 => SOL
* DIS # B3: 3 => CTR => B3: 5,6
* PRF # I7: 3,5 => SOL
* DIS # I7: 6 => CTR => I7: 3,5
* DIS # I7: 5,6 => CTR => I7: 3
* PRF # I7: 3 => SOL
* DIS # H5: 3 => CTR => H5: 5,6
* CNT  38 HDP CHAINS /  52 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A6,A7,B1,B8,C3,C5,D3,D9,F3,F6,F9,G4,G7,H2,H8,I1,I3)
* 9.715.68.4.8.7.1..1...8.27.284.9..1771.4289...9.71.842.79841.2.8.29374.1341.6.798
* PAIR B1: 2,3 BLK 1
B2: 2,3,6                                # reduction candidate for 2,3
B2: 6 => CTR
* 92715468346837215.13568.27.284.96.177134289..596713842679841.2.852937461341.65798
* PAIR C3: 5,6 COL C
C6: 5,6,3                                # reduction candidate for 5,6
C6: 5,6 => SOLVED
* 937152684428679135165384279284596317713428956596713842679841523852937461341265798
* DURATION: 0:00:04.317630  START: 15:14:44.684793  END: 15:14:49.002423 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-363-base-pr-001.dot
* REASONING
* DIS # B2: 6 => CTR => B2: 2,3
* PRF B2: 2,3 # C6: 5,6 => SOL
* STA B2: 2,3 + C6: 5,6
* CNT   2 HDP CHAINS /   3 HYP OPENED

Header Info

Top 500 Minimum 17 363

solution: 937152684428679135165384279284596317713428956596713842679841523852937461341265798
info: 4950     FNBHWY   S8.f     43452

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

Solution

position: 937152684428679135165384279284596317713428956596713842679841523852937461341265798 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 # B2: 2,3 => UNS
* DIS # B2: 6 => CTR => B2: 2,3
* INC # F1: 2,3 => UNS
* DIS # F1: 4 => CTR => F1: 2,3
* INC # B3: 5,6 => UNS
* DIS # B3: 3 => CTR => B3: 5,6
* PRF # C6: 5,6 => SOL
* DIS # C6: 3 => CTR => C6: 5,6
* PRF # D2: 3,6 => SOL
* INC # D2: 2 => UNS
* DIS # F2: 3,6 => CTR => F2: 2,9
* INC # F2: 2,9 => UNS
* PRF # B3: 3,6 => SOL
* DIS # B3: 5 => CTR => B3: 3,6
* INC # D4: 3,6 => UNS
* PRF # D4: 5 => SOL
* INC # F1: 3,4 => UNS
* PRF # F1: 2 => SOL
* INC # I2: 3,5 => UNS
* DIS # I2: 9 => CTR => I2: 3,5
* PRF # H5: 3,5 => SOL
* DIS # H5: 6 => CTR => H5: 3,5
* DIS # C6: 3,5 => CTR => C6: 6
* PRF # C6: 6 => SOL
* PRF # H5: 3,5 => SOL
* DIS # H5: 6 => CTR => H5: 3,5
* DIS # I5: 3,5 => CTR => I5: 6
* PRF # I5: 6 => SOL
* PRF # C6: 5,6 => SOL
* DIS # C6: 3 => CTR => C6: 5,6
* INC # D4: 3,5 => UNS
* DIS # F4: 3,5 => CTR => F4: 6
* INC # F4: 6 => UNS
* DIS # C6: 3,5 => CTR => C6: 6
* PRF # C6: 6 => SOL
* PRF # H5: 3,5 => SOL
* DIS # H5: 6 => CTR => H5: 3,5
* DIS # I5: 3,5 => CTR => I5: 6
* PRF # I5: 6 => SOL
* INC # D4: 3,5 => UNS
* DIS # F4: 3,5 => CTR => F4: 6
* INC # F4: 6 => UNS
* DIS # I7: 5,6 => CTR => I7: 3
* PRF # I7: 3 => SOL
* INC # B3: 5,6 => UNS
* DIS # B3: 3 => CTR => B3: 5,6
* PRF # I7: 3,5 => SOL
* DIS # I7: 6 => CTR => I7: 3,5
* DIS # I7: 5,6 => CTR => I7: 3
* PRF # I7: 3 => SOL
* INC # H5: 5,6 => UNS
* DIS # H5: 3 => CTR => H5: 5,6
* CNT  52 HDP CHAINS /  52 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* INC # B2: 2,3 => UNS
* DIS # B2: 6 => CTR => B2: 2,3
* PRF B2: 2,3 # C6: 5,6 => SOL
* STA B2: 2,3 + C6: 5,6
* CNT   3 HDP CHAINS /   3 HYP OPENED