Analysis of xx-top500-046-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: .4..35...6.....1...........1..2.......8.....4.......3..35....7....64.2.....1..... initial

Autosolve

position: .41.35.266..4..1.33.2...4..1.32.456.5283...14.645...32435...671.1.6432..2.615734. autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* DIS # B2: 8,9 => CTR => B2: 5,7
* DIS # B3: 8,9 => CTR => B3: 5
* PRF # D1: 8,9 => SOL
* PRF # A8: 8,9 => SOL
* DIS # A8: 7 => CTR => A8: 8,9
* PRF # B2: 7,9 => SOL
* DIS # B2: 5,8 => CTR => B2: 7,9
* DIS # E4: 7,9 => CTR => E4: 8
* PRF # B2: 7,9 => SOL
* DIS # B2: 5,8 => CTR => B2: 7,9
* DIS # E6: 7,9 => CTR => E6: 1,8
* DIS # G6: 7,9 => CTR => G6: 8
* PRF # A8: 7,9 => SOL
* DIS # A8: 8 => CTR => A8: 7,9
* DIS # G6: 7,9 => CTR => G6: 8
* DIS # G1: 8 => CTR => G1: 7,9
* PRF # A8: 7,9 => SOL
* DIS # A8: 8 => CTR => A8: 7,9
* PRF # A8: 8,9 => SOL
* DIS # A8: 7 => CTR => A8: 8,9
* DIS # B2: 8,9 => CTR => B2: 5,7
* DIS # B3: 8,9 => CTR => B3: 5
* PRF # D1: 8,9 => SOL
* DIS # I8: 8,9 => CTR => I8: 5
* PRF # I3: 8,9 => SOL
* CNT  25 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 # B2: 8,9 => CTR => B2: 5,7
* DIS B2: 5,7 # B3: 8,9 => CTR => B3: 5
* PRF B2: 5,7 + B3: 5 => SOL
* STA B2: 5,7 + B3: 5
* CNT   3 HDP CHAINS /   2 HYP OPENED

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

Details

Positions

.4..35...6.....1...........1..2.......8.....4.......3..35....7....64.2.....1..... initial
.41.35.266..4..1.33.2...4..1.32.456.5283...14.645...32435...671.1.6432..2.615734. autosolve
841935726679428153352761498193284567528376914764519832435892671917643285286157349 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (12)
A1: 8,9
C2: 7,9
E3: 1,6
F3: 1,6
B4: 7,9
A6: 7,9
F5: 6,9
G5: 7,9
C8: 7,9
B9: 8,9
D7: 8,9
I9: 8,9

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
E3,F3: 1.. / E3 = 1  => 19 pairs (_) / F3 = 1  => 11 pairs (_)
E6,F6: 1.. / E6 = 1  => 11 pairs (_) / F6 = 1  => 19 pairs (_)
E3,E6: 1.. / E3 = 1  => 19 pairs (_) / E6 = 1  => 11 pairs (_)
F3,F6: 1.. / F3 = 1  => 11 pairs (_) / F6 = 1  => 19 pairs (_)
E2,F2: 2.. / E2 = 2  => 14 pairs (_) / F2 = 2  => 14 pairs (_)
E7,F7: 2.. / E7 = 2  => 14 pairs (_) / F7 = 2  => 14 pairs (_)
E2,E7: 2.. / E2 = 2  => 14 pairs (_) / E7 = 2  => 14 pairs (_)
F2,F7: 2.. / F2 = 2  => 14 pairs (_) / F7 = 2  => 14 pairs (_)
B2,B3: 5.. / B2 = 5  =>  0 pairs (X) / B3 = 5  => 14 pairs (_)
H8,I8: 5.. / H8 = 5  =>  0 pairs (X) / I8 = 5  => 13 pairs (_)
B2,H2: 5.. / B2 = 5  =>  0 pairs (X) / H2 = 5  => 14 pairs (_)
I3,I8: 5.. / I3 = 5  =>  0 pairs (X) / I8 = 5  => 13 pairs (_)
E3,F3: 6.. / E3 = 6  => 11 pairs (_) / F3 = 6  => 19 pairs (_)
E5,F5: 6.. / E5 = 6  => 19 pairs (_) / F5 = 6  => 11 pairs (_)
E3,E5: 6.. / E3 = 6  => 11 pairs (_) / E5 = 6  => 19 pairs (_)
F3,F5: 6.. / F3 = 6  => 19 pairs (_) / F5 = 6  => 11 pairs (_)
B2,C2: 7.. / B2 = 7  =>  0 pairs (*) / C2 = 7  =>  0 pairs (X)
D1,D3: 7.. / D1 = 7  => 16 pairs (_) / D3 = 7  =>  0 pairs (*)
G1,I3: 7.. / G1 = 7  =>  0 pairs (*) / I3 = 7  =>  0 pairs (X)
B4,A6: 7.. / B4 = 7  =>  0 pairs (X) / A6 = 7  =>  0 pairs (_)
A8,C8: 7.. / A8 = 7  =>  0 pairs (X) / C8 = 7  =>  0 pairs (_)
D1,G1: 7.. / D1 = 7  => 16 pairs (_) / G1 = 7  =>  0 pairs (*)
D3,I3: 7.. / D3 = 7  =>  0 pairs (*) / I3 = 7  =>  0 pairs (X)
E5,G5: 7.. / E5 = 7  => 13 pairs (_) / G5 = 7  => 19 pairs (_)
A6,A8: 7.. / A6 = 7  =>  0 pairs (*) / A8 = 7  =>  0 pairs (X)
B2,B4: 7.. / B2 = 7  =>  0 pairs (*) / B4 = 7  =>  0 pairs (X)
C2,C8: 7.. / C2 = 7  =>  0 pairs (X) / C8 = 7  =>  0 pairs (_)
I3,I4: 7.. / I3 = 7  => 16 pairs (_) / I4 = 7  =>  0 pairs (*)
I4,G6: 8.. / I4 = 8  =>  0 pairs (X) / G6 = 8  => 21 pairs (_)
A8,B9: 8.. / A8 = 8  =>  0 pairs (X) / B9 = 8  =>  0 pairs (_)
E4,I4: 8.. / E4 = 8  => 21 pairs (_) / I4 = 8  =>  0 pairs (X)
B9,I9: 8.. / B9 = 8  =>  0 pairs (*) / I9 = 8  =>  0 pairs (X)
A1,A8: 8.. / A1 = 8  =>  0 pairs (*) / A8 = 8  =>  0 pairs (X)
G1,G6: 8.. / G1 = 8  =>  0 pairs (X) / G6 = 8  => 21 pairs (_)
B4,A6: 9.. / B4 = 9  =>  0 pairs (*) / A6 = 9  =>  0 pairs (X)
B9,I9: 9.. / B9 = 9  =>  0 pairs (X) / I9 = 9  =>  0 pairs (_)
C2,C8: 9.. / C2 = 9  =>  0 pairs (*) / C8 = 9  =>  0 pairs (X)
* DURATION: 0:01:02.763167  START: 04:14:03.370072  END: 04:15:06.133239 2017-05-04
* CP COUNT: (37)
* SOLUTION FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A1,A6,B4,B9,C2,C8,D7,E3,F3,F5,G5,I9)
* .41.35.266..4..1.33.2...4..1.32.456.5283...14.645...32435...671.1.6432..2.615734.
* PAIR A1: 8,9 BLK 1
B2: 8,9,5,7                              # reduction candidate for 8,9
B2: 8,9 => CTR
* 841.35.266974..153352...49.1732.456.5283...149645...32435...671719643285286157349
B2: 5,7                                  # 13 pairs
B3: 8,9,5                                # reduction candidate for 8,9
B3: 8,9 => CTR
* 841.35.266574..1.3392...4.71732945685283.69149645...32435...6717196432..286157349
B3: 5                                    # 14 pairs
* PAIR A1: 8,9 ROW 1
D1: 8,9,7                                # reduction candidate for 8,9
D1: 8,9 => SOLVED
* 841935726679428153352761498193284567528376914764519832435892671917643285286157349
D1: 7                                    # 16 pairs
G1: 8,9,7                                # reduction candidate for 8,9
G1: 8,9                                  # 16 pairs
* PAIR A1: 8,9 COL A
A8: 8,9,7                                # reduction candidate for 8,9
A8: 8,9 => SOLVED
* 841935726679428153352761498193284567528376914764519832435892671917643285286157349
A8: 7 => CTR
* 841.35.266..4..1.33.2...4..1.32.456.5283...149645..832435...6717196432..286157349
* PAIR C2: 7,9 BLK 1
B2: 7,9,5,8                              # reduction candidate for 7,9
B2: 7,9 => SOLVED
* 841935726679428153352761498193284567528376914764519832435892671917643285286157349
B2: 5,8 => CTR
* 841.35.266574..1.3392...4.71732945685283.69149645...32435...6717196432..286157349
* PAIR B4: 7,9 ROW 4
E4: 7,9,8                                # reduction candidate for 7,9
E4: 7,9 => CTR
* 841.35.266..4..1.33.28..4.71.32.45685283...14.645...324359..671.1.643285286157349
E4: 8                                    # 21 pairs
I4: 7,9,8                                # reduction candidate for 7,9
I4: 7,9                                  # 21 pairs
* PAIR B4: 7,9 COL B
B2: 7,9,5,8                              # reduction candidate for 7,9
B2: 7,9 => SOLVED
* 841935726679428153352761498193284567528376914764519832435892671917643285286157349
B2: 5,8 => CTR
* 841.35.266574..1.3392...4.71732945685283.69149645...32435...6717196432..286157349
* PAIR A6: 7,9 ROW 6
E6: 7,9,1,8                              # reduction candidate for 7,9
E6: 7,9 => CTR
* .41.35.266..4..1.33.2.164..1.32.456.528369714.64571832435...6717196432..286157349
E6: 1,8                                  # 13 pairs
G6: 7,9,8                                # reduction candidate for 7,9
G6: 7,9 => CTR
* .41.358266..4..1.33.2...4.71.32.45685283...14.645...32435...6718176432.529615734.
G6: 8                                    # 21 pairs
* PAIR A6: 7,9 COL A
A8: 7,9,8                                # reduction candidate for 7,9
A8: 7,9 => SOLVED
* 841935726679428153352761498193284567528376914764519832435892671917643285286157349
A8: 8 => CTR
* .41.35.266..4..1.33.2...4..1.32.456.5283...147645...32435...6718176432..29615734.
* PAIR F5: 6,9 BLK 5
E5: 6,9,7                                # reduction candidate for 6,9
E5: 6,9                                  # 19 pairs
E5: 7                                    # 13 pairs
* PAIR G5: 7,9 BLK 6
I4: 7,9,8                                # reduction candidate for 7,9
I4: 7,9                                  # 21 pairs
G6: 7,9,8                                # reduction candidate for 7,9
G6: 7,9 => CTR
* .41.358266..4..1.33.2...4.71.32.45685283...14.645...32435...6718176432.529615734.
G6: 8                                    # 21 pairs
* PAIR G5: 7,9 ROW 5
E5: 7,9,6                                # reduction candidate for 7,9
E5: 6                                    # 19 pairs
E5: 7,9                                  # 11 pairs
* PAIR G5: 7,9 COL G
G1: 7,9,8                                # reduction candidate for 7,9
G1: 8 => CTR
* .417358266..4..1.33.2...4.71.32.45685283...14.645...32435...6718176432.529615734.
G1: 7,9                                  # 21 pairs
* PAIR C8: 7,9 BLK 7
A8: 7,9,8                                # reduction candidate for 7,9
A8: 7,9 => SOLVED
* 841935726679428153352761498193284567528376914764519832435892671917643285286157349
A8: 8 => CTR
* .41.35.266..4..1.33.2...4..1.32.456.5283...147645...32435...6718176432..29615734.
* PAIR B9: 8,9 BLK 7
A8: 8,9,7                                # reduction candidate for 8,9
A8: 8,9 => SOLVED
* 841935726679428153352761498193284567528376914764519832435892671917643285286157349
A8: 7 => CTR
* 841.35.266..4..1.33.2...4..1.32.456.5283...149645..832435...6717196432..286157349
* PAIR B9: 8,9 COL B
B2: 8,9,5,7                              # reduction candidate for 8,9
B2: 8,9 => CTR
* 841.35.266974..153352...49.1732.456.5283...149645...32435...671719643285286157349
B2: 5,7                                  # 13 pairs
B3: 8,9,5                                # reduction candidate for 8,9
B3: 8,9 => CTR
* 841.35.266574..1.3392...4.71732945685283.69149645...32435...6717196432..286157349
B3: 5                                    # 14 pairs
* PAIR D7: 8,9 BLK 8
E7: 8,9,2                                # reduction candidate for 8,9
E7: 8,9                                  # 14 pairs
F7: 8,9,2                                # reduction candidate for 8,9
F7: 8,9                                  # 14 pairs
* PAIR D7: 8,9 COL D
D1: 8,9,7                                # reduction candidate for 8,9
D1: 8,9 => SOLVED
* 841935726679428153352761498193284567528376914764519832435892671917643285286157349
D1: 7                                    # 16 pairs
D3: 8,9,7                                # reduction candidate for 8,9
D3: 8,9                                  # 16 pairs
* PAIR I9: 8,9 BLK 9
H8: 8,9,5                                # reduction candidate for 8,9
H8: 8,9                                  # 13 pairs
I8: 8,9,5                                # reduction candidate for 8,9
I8: 8,9 => CTR
* .41.35.266..4..1.33.2...4.51.32.45675283769147645..832435...671.1764325.2.615734.
I8: 5                                    # 13 pairs
* PAIR I9: 8,9 COL I
I3: 8,9,5,7                              # reduction candidate for 8,9
I3: 8,9 => SOLVED
* 841935726679428153352761498193284567528376914764519832435892671917643285286157349
I3: 5,7                                  # 13 pairs
I4: 8,9,7                                # reduction candidate for 8,9
I4: 8,9                                  # 16 pairs
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-046-base-pr-000.dot
* REASONING
* DIS # B2: 8,9 => CTR => B2: 5,7
* DIS # B3: 8,9 => CTR => B3: 5
* PRF # D1: 8,9 => SOL
* PRF # A8: 8,9 => SOL
* DIS # A8: 7 => CTR => A8: 8,9
* PRF # B2: 7,9 => SOL
* DIS # B2: 5,8 => CTR => B2: 7,9
* DIS # E4: 7,9 => CTR => E4: 8
* PRF # B2: 7,9 => SOL
* DIS # B2: 5,8 => CTR => B2: 7,9
* DIS # E6: 7,9 => CTR => E6: 1,8
* DIS # G6: 7,9 => CTR => G6: 8
* PRF # A8: 7,9 => SOL
* DIS # A8: 8 => CTR => A8: 7,9
* DIS # G6: 7,9 => CTR => G6: 8
* DIS # G1: 8 => CTR => G1: 7,9
* PRF # A8: 7,9 => SOL
* DIS # A8: 8 => CTR => A8: 7,9
* PRF # A8: 8,9 => SOL
* DIS # A8: 7 => CTR => A8: 8,9
* DIS # B2: 8,9 => CTR => B2: 5,7
* DIS # B3: 8,9 => CTR => B3: 5
* PRF # D1: 8,9 => SOL
* DIS # I8: 8,9 => CTR => I8: 5
* PRF # I3: 8,9 => SOL
* CNT  25 HDP CHAINS /  50 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A1,A6,B4,B9,C2,C8,D7,E3,F3,F5,G5,I9)
* .41.35.266..4..1.33.2...4..1.32.456.5283...14.645...32435...671.1.6432..2.615734.
* PAIR A1: 8,9 BLK 1
B2: 8,9,5,7                              # reduction candidate for 8,9
B2: 8,9 => CTR
* 841.35.266974..153352...49.1732.456.5283...149645...32435...671719643285286157349
B3: 8,9,5                                # reduction candidate for 8,9
B3: 8,9 => CTR
* 841.35.266574..1.3392...4.71732945685283.69149645...32435...6717196432..286157349
B3: 5 => SOLVED
* 841935726679428153352761498193284567528376914764519832435892671917643285286157349
* DURATION: 0:00:02.818963  START: 04:15:54.962086  END: 04:15:57.781049 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-046-base-pr-001.dot
* REASONING
* DIS # B2: 8,9 => CTR => B2: 5,7
* DIS B2: 5,7 # B3: 8,9 => CTR => B3: 5
* PRF B2: 5,7 + B3: 5 => SOL
* STA B2: 5,7 + B3: 5
* CNT   3 HDP CHAINS /   2 HYP OPENED

Header Info

Top 500 Minimum 17 046

solution: 841935726679428153352761498193284567528376914764519832435892671917643285286157349
info: 1378     FNBTHWXY S8.f     18884

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

Solution

position: 841935726679428153352761498193284567528376914764519832435892671917643285286157349 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:

* DIS # B2: 8,9 => CTR => B2: 5,7
* INC # B2: 5,7 => UNS
* DIS # B3: 8,9 => CTR => B3: 5
* INC # B3: 5 => UNS
* PRF # D1: 8,9 => SOL
* INC # D1: 7 => UNS
* INC # G1: 8,9 => UNS
* PRF # A8: 8,9 => SOL
* DIS # A8: 7 => CTR => A8: 8,9
* PRF # B2: 7,9 => SOL
* DIS # B2: 5,8 => CTR => B2: 7,9
* DIS # E4: 7,9 => CTR => E4: 8
* INC # E4: 8 => UNS
* INC # I4: 7,9 => UNS
* PRF # B2: 7,9 => SOL
* DIS # B2: 5,8 => CTR => B2: 7,9
* DIS # E6: 7,9 => CTR => E6: 1,8
* INC # E6: 1,8 => UNS
* DIS # G6: 7,9 => CTR => G6: 8
* INC # G6: 8 => UNS
* PRF # A8: 7,9 => SOL
* DIS # A8: 8 => CTR => A8: 7,9
* INC # E5: 6,9 => UNS
* INC # E5: 7 => UNS
* INC # I4: 7,9 => UNS
* DIS # G6: 7,9 => CTR => G6: 8
* INC # G6: 8 => UNS
* INC # E5: 7,9 => UNS
* INC # E5: 6 => UNS
* INC # G1: 7,9 => UNS
* DIS # G1: 8 => CTR => G1: 7,9
* PRF # A8: 7,9 => SOL
* DIS # A8: 8 => CTR => A8: 7,9
* PRF # A8: 8,9 => SOL
* DIS # A8: 7 => CTR => A8: 8,9
* DIS # B2: 8,9 => CTR => B2: 5,7
* INC # B2: 5,7 => UNS
* DIS # B3: 8,9 => CTR => B3: 5
* INC # B3: 5 => UNS
* INC # E7: 8,9 => UNS
* INC # F7: 8,9 => UNS
* PRF # D1: 8,9 => SOL
* INC # D1: 7 => UNS
* INC # D3: 8,9 => UNS
* INC # H8: 8,9 => UNS
* DIS # I8: 8,9 => CTR => I8: 5
* INC # I8: 5 => UNS
* PRF # I3: 8,9 => SOL
* INC # I3: 5,7 => UNS
* INC # I4: 8,9 => UNS
* CNT  50 HDP CHAINS /  50 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* DIS # B2: 8,9 => CTR => B2: 5,7
* DIS B2: 5,7 # B3: 8,9 => CTR => B3: 5
* PRF B2: 5,7 + B3: 5 => SOL
* STA B2: 5,7 + B3: 5
* CNT   3 HDP CHAINS /   2 HYP OPENED