Analysis of xx-top500-377-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: .84.6.......7...3..........73.1...........6.1......8....6.4.2..1..3...5.......... initial

Autosolve

position: .84.631.761.7...3..73....6.73.186.4.8.5.3.671461.7.8.33568472191483..756..76..384 autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* DIS # F2: 2,9 => CTR => F2: 4,5,8
* DIS # G2: 5,9 => CTR => G2: 4
* DIS # E3: 2,9 => CTR => E3: 1,5
* DIS # F2: 2,9 => CTR => F2: 4,5,8
* PRF # F3: 2,9 => SOL
* DIS # E3: 2,9 => CTR => E3: 1,5
* CNT   6 HDP CHAINS /  31 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 # F2: 2,9 => CTR => F2: 4,5,8
* DIS F2: 4,5,8 # E2: 5 => CTR => E2: 2,9
* DIS F2: 4,5,8 + E2: 2,9 # G3: 4 => CTR => G3: 5,9
* PRF F2: 4,5,8 + E2: 2,9 + G3: 5,9 # I3: 8 => SOL
* STA F2: 4,5,8 + E2: 2,9 + G3: 5,9 + I3: 8
* CNT   4 HDP CHAINS /  16 HYP OPENED

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

Details

Positions

.84.6.......7...3..........73.1...........6.1......8....6.4.2..1..3...5.......... initial
.84.631.761.7...3..73....6.73.186.4.8.5.3.671461.7.8.33568472191483..756..76..384 autosolve
984563127612798435573412968739186542825934671461275893356847219148329756297651384 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (13)
C2: 2,9
H1: 2,9
C4: 2,9
B5: 2,9
G4: 5,9
I4: 2,5
H6: 2,9
A9: 2,9
B9: 2,9
E8: 2,9
F8: 2,9
E9: 1,5
F9: 1,5

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
E3,F3: 1.. / E3 = 1  => 14 pairs (_) / F3 = 1  => 17 pairs (_)
E9,F9: 1.. / E9 = 1  => 17 pairs (_) / F9 = 1  => 14 pairs (_)
E3,E9: 1.. / E3 = 1  => 14 pairs (_) / E9 = 1  => 17 pairs (_)
F3,F9: 1.. / F3 = 1  => 17 pairs (_) / F9 = 1  => 14 pairs (_)
C4,B5: 2.. / C4 = 2  => 19 pairs (_) / B5 = 2  => 19 pairs (_)
I4,H6: 2.. / I4 = 2  => 19 pairs (_) / H6 = 2  => 19 pairs (_)
A9,B9: 2.. / A9 = 2  => 19 pairs (_) / B9 = 2  => 19 pairs (_)
E8,F8: 2.. / E8 = 2  => 15 pairs (_) / F8 = 2  => 15 pairs (_)
C4,I4: 2.. / C4 = 2  => 19 pairs (_) / I4 = 2  => 19 pairs (_)
B5,B9: 2.. / B5 = 2  => 19 pairs (_) / B9 = 2  => 19 pairs (_)
C2,C4: 2.. / C2 = 2  => 19 pairs (_) / C4 = 2  => 19 pairs (_)
H1,H6: 2.. / H1 = 2  => 19 pairs (_) / H6 = 2  => 19 pairs (_)
G2,G3: 4.. / G2 = 4  => 14 pairs (_) / G3 = 4  =>  0 pairs (X)
D5,F5: 4.. / D5 = 4  => 20 pairs (_) / F5 = 4  => 15 pairs (_)
F2,G2: 4.. / F2 = 4  =>  0 pairs (X) / G2 = 4  => 14 pairs (_)
D3,D5: 4.. / D3 = 4  => 15 pairs (_) / D5 = 4  => 20 pairs (_)
A1,A3: 5.. / A1 = 5  => 15 pairs (_) / A3 = 5  => 19 pairs (_)
D6,F6: 5.. / D6 = 5  => 19 pairs (_) / F6 = 5  => 18 pairs (_)
G4,I4: 5.. / G4 = 5  => 19 pairs (_) / I4 = 5  => 19 pairs (_)
E9,F9: 5.. / E9 = 5  => 14 pairs (_) / F9 = 5  => 17 pairs (_)
A1,D1: 5.. / A1 = 5  => 15 pairs (_) / D1 = 5  => 19 pairs (_)
F2,F3: 8.. / F2 = 8  => 15 pairs (_) / F3 = 8  => 15 pairs (_)
I2,I3: 8.. / I2 = 8  => 15 pairs (_) / I3 = 8  => 15 pairs (_)
F2,I2: 8.. / F2 = 8  => 15 pairs (_) / I2 = 8  => 15 pairs (_)
F3,I3: 8.. / F3 = 8  => 15 pairs (_) / I3 = 8  => 15 pairs (_)
C4,B5: 9.. / C4 = 9  => 19 pairs (_) / B5 = 9  => 19 pairs (_)
G4,H6: 9.. / G4 = 9  => 19 pairs (_) / H6 = 9  => 19 pairs (_)
A9,B9: 9.. / A9 = 9  => 19 pairs (_) / B9 = 9  => 19 pairs (_)
E8,F8: 9.. / E8 = 9  => 15 pairs (_) / F8 = 9  => 15 pairs (_)
C4,G4: 9.. / C4 = 9  => 19 pairs (_) / G4 = 9  => 19 pairs (_)
B5,B9: 9.. / B5 = 9  => 19 pairs (_) / B9 = 9  => 19 pairs (_)
C2,C4: 9.. / C2 = 9  => 19 pairs (_) / C4 = 9  => 19 pairs (_)
H1,H6: 9.. / H1 = 9  => 19 pairs (_) / H6 = 9  => 19 pairs (_)
* DURATION: 0:01:09.385744  START: 15:46:07.610513  END: 15:47:16.996257 2017-05-04
* CP COUNT: (33)
* CLUE FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A9,B5,B9,C2,C4,E8,E9,F8,F9,G4,H1,H6,I4)
* .84.631.761.7...3..73....6.73.186.4.8.5.3.671461.7.8.33568472191483..756..76..384
* PAIR C2: 2,9 BLK 1
A1: 2,9,5                                # reduction candidate for 2,9
A1: 2,9                                  # 19 pairs
A3: 2,9,5                                # reduction candidate for 2,9
A3: 2,9                                  # 15 pairs
* PAIR C2: 2,9 ROW 2
E2: 2,9,5                                # reduction candidate for 2,9
E2: 2,9                                  # 17 pairs
F2: 2,9,4,5,8                            # reduction candidate for 2,9
F2: 2,9 => CTR
* .84.631.761.75.438.73..8.6.73.186.4.8.5.34671461.7.8.33568472191483..756..76.1384
F2: 4,5,8                                # 13 pairs
* PAIR H1: 2,9 ROW 1
A1: 2,9,5                                # reduction candidate for 2,9
A1: 2,9                                  # 19 pairs
D1: 2,9,5                                # reduction candidate for 2,9
D1: 2,9                                  # 15 pairs
* PAIR B5: 2,9 ROW 5
D5: 2,9,4                                # reduction candidate for 2,9
D5: 2,9                                  # 15 pairs
F5: 2,9,4                                # reduction candidate for 2,9
F5: 2,9                                  # 20 pairs
* PAIR G4: 5,9 COL G
G2: 5,9,4                                # reduction candidate for 5,9
G2: 5,9 => CTR
* .84.631.761.7.4538.73.1846273218694589543267146197582335684721914832.756..7651384
G2: 4                                    # 14 pairs
G3: 5,9,4                                # reduction candidate for 5,9
G3: 5,9                                  # 14 pairs
* PAIR I4: 2,5 COL I
I2: 2,5,8                                # reduction candidate for 2,5
I2: 2,5                                  # 15 pairs
I3: 2,5,8                                # reduction candidate for 2,5
I3: 2,5                                  # 15 pairs
* PAIR H6: 2,9 ROW 6
D6: 2,9,5                                # reduction candidate for 2,9
D6: 2,9                                  # 18 pairs
F6: 2,9,5                                # reduction candidate for 2,9
F6: 2,9                                  # 19 pairs
* PAIR A9: 2,9 COL A
A1: 2,9,5                                # reduction candidate for 2,9
A1: 2,9                                  # 19 pairs
A3: 2,9,5                                # reduction candidate for 2,9
A3: 2,9                                  # 15 pairs
* PAIR E8: 2,9 COL E
E2: 2,9,5                                # reduction candidate for 2,9
E2: 2,9                                  # 17 pairs
E3: 2,9,1,5                              # reduction candidate for 2,9
E3: 2,9 => CTR
* .84.631.761.758432.734.15687321869458952346714615798233568472191483927569.7615384
E3: 1,5                                  # 17 pairs
* PAIR F8: 2,9 COL F
F2: 2,9,4,5,8                            # reduction candidate for 2,9
F2: 2,9 => CTR
* .84.631.761.75.438.73..8.6.73.186.4.8.5.34671461.7.8.33568472191483..756..76.1384
F2: 4,5,8                                # 13 pairs
F3: 2,9,1,4,5,8                          # reduction candidate for 2,9
F3: 2,9 => SOLVED
* 984563127612798435573412968739186542825934671461275893356847219148329756297651384
F3: 1,4,5,8                              # 13 pairs
F5: 2,9,4                                # reduction candidate for 2,9
F5: 2,9                                  # 20 pairs
F6: 2,9,5                                # reduction candidate for 2,9
F6: 2,9                                  # 19 pairs
* PAIR E9: 1,5 COL E
E3: 1,5,2,9                              # reduction candidate for 1,5
E3: 2,9 => CTR
* .84.631.761.758432.734.15687321869458952346714615798233568472191483927569.7615384
E3: 1,5                                  # 17 pairs
* PAIR F9: 1,5 COL F
F3: 1,5,2,4,8,9                          # reduction candidate for 1,5
F3: 1,5                                  # 20 pairs
F3: 2,4,8,9                              # 14 pairs
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-377-base-pr-000.dot
* REASONING
* DIS # F2: 2,9 => CTR => F2: 4,5,8
* DIS # G2: 5,9 => CTR => G2: 4
* DIS # E3: 2,9 => CTR => E3: 1,5
* DIS # F2: 2,9 => CTR => F2: 4,5,8
* PRF # F3: 2,9 => SOL
* DIS # E3: 2,9 => CTR => E3: 1,5
* CNT   6 HDP CHAINS /  31 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A9,B5,B9,C2,C4,E8,E9,F8,F9,G4,H1,H6,I4)
* .84.631.761.7...3..73....6.73.186.4.8.5.3.671461.7.8.33568472191483..756..76..384
* PAIR C2: 2,9 BLK 1
A1: 2,9,5                                # reduction candidate for 2,9
A1: 2,9                                  # 19 pairs
A3: 2,9,5                                # reduction candidate for 2,9
A3: 2,9                                  # 15 pairs
* PAIR C2: 2,9 ROW 2
E2: 2,9,5                                # reduction candidate for 2,9
E2: 2,9                                  # 17 pairs
F2: 2,9,4,5,8                            # reduction candidate for 2,9
F2: 2,9 => CTR
* .84.631.761.75.438.73..8.6.73.186.4.8.5.34671461.7.8.33568472191483..756..76.1384
* RESTART
* PAIR C2: 2,9 ROW 2
E2: 2,9,5                                # reduction candidate for 2,9
E2: 5 => CTR
* 584263197619758432273491568732186945895.3.67146157.8233568472191483..756..7615384
* PAIR RESTART
* PAIR C2: 2,9 BLK 1
A1: 2,9,5                                # reduction candidate for 2,9
A1: 2,9                                  # 19 pairs
A3: 2,9,5                                # reduction candidate for 2,9
A3: 2,9                                  # 20 pairs
* PAIR H1: 2,9 ROW 1
A1: 2,9,5                                # reduction candidate for 2,9
A1: 2,9                                  # 19 pairs
D1: 2,9,5                                # reduction candidate for 2,9
D1: 2,9                                  # 20 pairs
* PAIR B5: 2,9 ROW 5
D5: 2,9,4                                # reduction candidate for 2,9
D5: 2,9                                  # 19 pairs
F5: 2,9,4                                # reduction candidate for 2,9
F5: 2,9                                  # 20 pairs
* PAIR G4: 5,9 COL G
G3: 5,9,4                                # reduction candidate for 5,9
G3: 4 => CTR
* .84.6319761.7...3..73...462732186945895432671461.7.8233568472191483297569276..384
* PAIR RESTART
* PAIR I4: 2,5 COL I
I3: 2,5,8                                # reduction candidate for 2,5
I3: 8 => SOLVED
* 984563127612798435573412968739186542825934671461275893356847219148329756297651384
* DURATION: 0:00:19.185446  START: 15:47:51.054505  END: 15:48:10.239951 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-377-base-pr-001.dot
* REASONING
* DIS # F2: 2,9 => CTR => F2: 4,5,8
* DIS F2: 4,5,8 # E2: 5 => CTR => E2: 2,9
* DIS F2: 4,5,8 + E2: 2,9 # G3: 4 => CTR => G3: 5,9
* PRF F2: 4,5,8 + E2: 2,9 + G3: 5,9 # I3: 8 => SOL
* STA F2: 4,5,8 + E2: 2,9 + G3: 5,9 + I3: 8
* CNT   4 HDP CHAINS /  16 HYP OPENED

Header Info

Top 500 Minimum 17 377

solution: 984563127612798435573412968739186542825934671461275893356847219148329756297651384
info: 18455    FNBXYK   S8.f     39367

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

Solution

position: 984563127612798435573412968739186542825934671461275893356847219148329756297651384 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 # A1: 2,9 => UNS
* INC # A3: 2,9 => UNS
* INC # E2: 2,9 => UNS
* DIS # F2: 2,9 => CTR => F2: 4,5,8
* INC # F2: 4,5,8 => UNS
* INC # A1: 2,9 => UNS
* INC # D1: 2,9 => UNS
* INC # D5: 2,9 => UNS
* INC # F5: 2,9 => UNS
* DIS # G2: 5,9 => CTR => G2: 4
* INC # G2: 4 => UNS
* INC # G3: 5,9 => UNS
* INC # I2: 2,5 => UNS
* INC # I3: 2,5 => UNS
* INC # D6: 2,9 => UNS
* INC # F6: 2,9 => UNS
* INC # A1: 2,9 => UNS
* INC # A3: 2,9 => UNS
* INC # E2: 2,9 => UNS
* DIS # E3: 2,9 => CTR => E3: 1,5
* INC # E3: 1,5 => UNS
* DIS # F2: 2,9 => CTR => F2: 4,5,8
* INC # F2: 4,5,8 => UNS
* PRF # F3: 2,9 => SOL
* INC # F3: 1,4,5,8 => UNS
* INC # F5: 2,9 => UNS
* INC # F6: 2,9 => UNS
* INC # E3: 1,5 => UNS
* DIS # E3: 2,9 => CTR => E3: 1,5
* INC # F3: 1,5 => UNS
* INC # F3: 2,4,8,9 => UNS
* CNT  31 HDP CHAINS /  31 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* INC # A1: 2,9 => UNS
* INC # A3: 2,9 => UNS
* INC # E2: 2,9 => UNS
* DIS # F2: 2,9 => CTR => F2: 4,5,8
* INC F2: 4,5,8 # E2: 2,9 => UNS
* DIS F2: 4,5,8 # E2: 5 => CTR => E2: 2,9
* INC F2: 4,5,8 + E2: 2,9 # A1: 2,9 => UNS
* INC F2: 4,5,8 + E2: 2,9 # A3: 2,9 => UNS
* INC F2: 4,5,8 + E2: 2,9 # A1: 2,9 => UNS
* INC F2: 4,5,8 + E2: 2,9 # D1: 2,9 => UNS
* INC F2: 4,5,8 + E2: 2,9 # D5: 2,9 => UNS
* INC F2: 4,5,8 + E2: 2,9 # F5: 2,9 => UNS
* INC F2: 4,5,8 + E2: 2,9 # G3: 5,9 => UNS
* DIS F2: 4,5,8 + E2: 2,9 # G3: 4 => CTR => G3: 5,9
* INC F2: 4,5,8 + E2: 2,9 + G3: 5,9 # I3: 2,5 => UNS
* PRF F2: 4,5,8 + E2: 2,9 + G3: 5,9 # I3: 8 => SOL
* STA F2: 4,5,8 + E2: 2,9 + G3: 5,9 + I3: 8
* CNT  16 HDP CHAINS /  16 HYP OPENED