Analysis of xx-top500-065-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: ....7..421..6............7.52.1.....3.....5......8.......3..6...74........8...... initial

Autosolve

position: 863.7..421976.....452....7652.1.....38....5..74..8.....153..6...74.......38...... autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* DIS # F7: 2,4 => CTR => F7: 7,8,9
* PRF # F5: 4,7 => SOL
* PRF # I5: 1,9 => SOL
* PRF # I4: 4,7 => SOL
* DIS # G8: 8 => CTR => G8: 2,3
* DIS # F7: 2,9 => CTR => F7: 4,7,8
* PRF # H7: 2,9 => SOL
* PRF # F7: 2,8,9 => SOL
* PRF # F7: 2,8,9 => SOL
* PRF # I4: 4,7 => SOL
* CNT  10 HDP CHAINS /  56 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 # F7: 2,4 => CTR => F7: 7,8,9
* PRF F7: 7,8,9 # F5: 4,7 => SOL
* STA F7: 7,8,9 + F5: 4,7
* CNT   2 HDP CHAINS /  31 HYP OPENED

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

Details

Positions

....7..421..6............7.52.1.....3.....5......8.......3..6...74........8...... initial
863.7..421976.....452....7652.1.....38....5..74..8.....153..6...74.......38...... autosolve
863579142197624853452813976529136784386497521741285369215348697674951238938762415 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (15)
D1: 5,9
E2: 2,4
F2: 2,4
D3: 8,9
G1: 1,9
G2: 3,8
G3: 1,9
C4: 6,9
D5: 4,7
G4: 4,7
G6: 2,3
A7: 2,9
D9: 4,7
I7: 4,7
G9: 4,7

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
G1,G3: 1.. / G1 = 1  => 16 pairs (_) / G3 = 1  => 16 pairs (_)
C5,C6: 1.. / C5 = 1  => 16 pairs (_) / C6 = 1  => 17 pairs (_)
F1,G1: 1.. / F1 = 1  => 16 pairs (_) / G1 = 1  => 16 pairs (_)
E2,F2: 2.. / E2 = 2  => 14 pairs (_) / F2 = 2  => 20 pairs (_)
D6,D8: 2.. / D6 = 2  => 19 pairs (_) / D8 = 2  => 17 pairs (_)
G6,G8: 2.. / G6 = 2  => 17 pairs (_) / G8 = 2  => 19 pairs (_)
E3,F3: 3.. / E3 = 3  => 17 pairs (_) / F3 = 3  => 16 pairs (_)
E3,E4: 3.. / E3 = 3  => 17 pairs (_) / E4 = 3  => 16 pairs (_)
E2,F2: 4.. / E2 = 4  => 20 pairs (_) / F2 = 4  => 14 pairs (_)
I7,G9: 4.. / I7 = 4  =>  0 pairs (X) / G9 = 4  =>  0 pairs (_)
D9,G9: 4.. / D9 = 4  =>  0 pairs (X) / G9 = 4  =>  0 pairs (_)
D5,D9: 4.. / D5 = 4  =>  0 pairs (*) / D9 = 4  =>  0 pairs (X)
G4,G9: 4.. / G4 = 4  =>  0 pairs (X) / G9 = 4  =>  0 pairs (_)
D1,F1: 5.. / D1 = 5  => 16 pairs (_) / F1 = 5  => 15 pairs (_)
H2,I2: 5.. / H2 = 5  => 16 pairs (_) / I2 = 5  => 17 pairs (_)
D6,F6: 5.. / D6 = 5  => 15 pairs (_) / F6 = 5  => 16 pairs (_)
E8,E9: 5.. / E8 = 5  => 15 pairs (_) / E9 = 5  => 16 pairs (_)
D1,D6: 5.. / D1 = 5  => 16 pairs (_) / D6 = 5  => 15 pairs (_)
F1,F6: 5.. / F1 = 5  => 15 pairs (_) / F6 = 5  => 16 pairs (_)
A8,A9: 6.. / A8 = 6  => 16 pairs (_) / A9 = 6  => 16 pairs (_)
F7,D9: 7.. / F7 = 7  =>  0 pairs (X) / D9 = 7  =>  0 pairs (_)
I7,G9: 7.. / I7 = 7  =>  0 pairs (*) / G9 = 7  =>  0 pairs (X)
F7,I7: 7.. / F7 = 7  =>  0 pairs (X) / I7 = 7  =>  0 pairs (_)
D9,G9: 7.. / D9 = 7  =>  0 pairs (*) / G9 = 7  =>  0 pairs (X)
D5,D9: 7.. / D5 = 7  =>  0 pairs (X) / D9 = 7  =>  0 pairs (_)
G4,G9: 7.. / G4 = 7  =>  0 pairs (*) / G9 = 7  =>  0 pairs (X)
D3,F3: 8.. / D3 = 8  => 15 pairs (_) / F3 = 8  =>  0 pairs (X)
H4,I4: 8.. / H4 = 8  =>  0 pairs (*) / I4 = 8  =>  0 pairs (X)
F7,H7: 8.. / F7 = 8  =>  0 pairs (*) / H7 = 8  =>  0 pairs (X)
D3,D8: 8.. / D3 = 8  => 15 pairs (_) / D8 = 8  =>  0 pairs (X)
G2,G8: 8.. / G2 = 8  => 17 pairs (_) / G8 = 8  =>  0 pairs (X)
G1,G3: 9.. / G1 = 9  => 16 pairs (_) / G3 = 9  => 16 pairs (_)
* DURATION: 0:00:57.168066  START: 04:51:51.085183  END: 04:52:48.253249 2017-05-04
* CP COUNT: (32)
* SOLUTION FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A7,C4,D1,D3,D5,D9,E2,F2,G1,G2,G3,G4,G6,G9,I7)
* 863.7..421976.....452....7652.1.....38....5..74..8.....153..6...74.......38......
* PAIR D1: 5,9 BLK 2
F1: 5,9,1                                # reduction candidate for 5,9
F1: 5,9                                  # 16 pairs
F1: 1                                    # 16 pairs
* PAIR D1: 5,9 COL D
D6: 5,9,2                                # reduction candidate for 5,9
D6: 2                                    # 19 pairs
D6: 5,9                                  # 17 pairs
* PAIR E2: 2,4 COL E
E5: 2,4,6,9                              # reduction candidate for 2,4
E5: 2,4                                  # 21 pairs
E7: 2,4,9                                # reduction candidate for 2,4
E7: 2,4                                  # 17 pairs
* PAIR F2: 2,4 COL F
F5: 2,4,6,7,9                            # reduction candidate for 2,4
F5: 2,4                                  # 16 pairs
F7: 2,4,7,8,9                            # reduction candidate for 2,4
F7: 2,4 => CTR
* 863.7..421976..8..452....7652.1..7.838.4.75..74..8.....153..687.74.......387..4..
F7: 7,8,9                                # 15 pairs
* PAIR D3: 8,9 BLK 2
F3: 8,9,1,3                              # reduction candidate for 8,9
F3: 8,9                                  # 16 pairs
F3: 1,3                                  # 16 pairs
* PAIR D3: 8,9 COL D
D8: 8,9,2                                # reduction candidate for 8,9
D8: 8,9                                  # 19 pairs
D8: 2                                    # 17 pairs
* PAIR G1: 1,9 ROW 1
F1: 1,9,5                                # reduction candidate for 1,9
F1: 1,9                                  # 16 pairs
F1: 5                                    # 15 pairs
* PAIR G2: 3,8 BLK 3
H2: 3,8,5                                # reduction candidate for 3,8
H2: 3,8                                  # 17 pairs
I2: 3,8,5                                # reduction candidate for 3,8
I2: 3,8                                  # 16 pairs
* PAIR G2: 3,8 COL G
G8: 3,8,2                                # reduction candidate for 3,8
G8: 2                                    # 19 pairs
G8: 3,8                                  # 17 pairs
* PAIR G3: 1,9 ROW 3
E3: 1,9,3                                # reduction candidate for 1,9
E3: 1,9                                  # 16 pairs
F3: 1,9,3,8                              # reduction candidate for 1,9
F3: 1,9                                  # 18 pairs
* PAIR C4: 6,9 BLK 4
C5: 6,9,1                                # reduction candidate for 6,9
C5: 6,9                                  # 17 pairs
C6: 6,9,1                                # reduction candidate for 6,9
C6: 6,9                                  # 16 pairs
* PAIR C4: 6,9 ROW 4
E4: 6,9,3,4                              # reduction candidate for 6,9
E4: 6,9                                  # 19 pairs
F4: 6,9,3,4,7                            # reduction candidate for 6,9
F4: 6,9                                  # 18 pairs
H4: 6,9,3,8                              # reduction candidate for 6,9
H4: 6,9                                  # 19 pairs
* PAIR D5: 4,7 BLK 5
F4: 4,7,3,6,9                            # reduction candidate for 4,7
F4: 4,7                                  # 17 pairs
F5: 4,7,2,6,9                            # reduction candidate for 4,7
F5: 4,7 => SOLVED
* 863579142197624853452813976529136784386497521741285369215348697674951238938762415
F5: 2,6,9                                # 15 pairs
* PAIR D5: 4,7 ROW 5
I5: 4,7,1,9                              # reduction candidate for 4,7
I5: 1,9 => SOLVED
* 863579142197624853452813976529136784386497521741285369215348697674951238938762415
I5: 4,7                                  # 16 pairs
* PAIR G4: 4,7 BLK 6
I4: 4,7,3,8,9                            # reduction candidate for 4,7
I4: 4,7 => SOLVED
* 863579142197624853452813976529136784386497521741285369215348697674951238938762415
I4: 3,8,9                                # 16 pairs
I5: 4,7,1,9                              # reduction candidate for 4,7
I5: 4,7                                  # 16 pairs
* PAIR G4: 4,7 ROW 4
F4: 4,7,3,6,9                            # reduction candidate for 4,7
F4: 4,7                                  # 17 pairs
F4: 3,6,9                                # 15 pairs
* PAIR G6: 2,3 BLK 6
H6: 2,3,1,6,9                            # reduction candidate for 2,3
H6: 2,3                                  # 19 pairs
H6: 1,6,9                                # 15 pairs
* PAIR G6: 2,3 ROW 6
F6: 2,3,5,6,9                            # reduction candidate for 2,3
F6: 2,3                                  # 21 pairs
F6: 5,6,9                                # 15 pairs
* PAIR G6: 2,3 COL G
G8: 2,3,8                                # reduction candidate for 2,3
G8: 8 => CTR
* 863.7..421976..3..4528...7652.1..7..38.4.75..74..8.2...153486.7.742..8...387..4..
G8: 2,3                                  # 17 pairs
* PAIR A7: 2,9 BLK 7
A8: 2,9,6                                # reduction candidate for 2,9
A8: 2,9                                  # 16 pairs
A9: 2,9,6                                # reduction candidate for 2,9
A9: 2,9                                  # 16 pairs
* PAIR A7: 2,9 ROW 7
E7: 2,9,4                                # reduction candidate for 2,9
E7: 2,9                                  # 20 pairs
F7: 2,9,4,7,8                            # reduction candidate for 2,9
F7: 2,9 => CTR
* 863.7..421976..8..452....7652.1..7.838.4.75..74..8.....1534.687.74.......387..4..
F7: 4,7,8                                # 15 pairs
H7: 2,9,8                                # reduction candidate for 2,9
H7: 2,9 => SOLVED
* 863579142197624853452813976529136784386497521741285369215348697674951238938762415
H7: 8                                    # 18 pairs
* PAIR D9: 4,7 BLK 8
F7: 4,7,2,8,9                            # reduction candidate for 4,7
F7: 2,8,9 => SOLVED
* 863579142197624853452813976529136784386497521741285369215348697674951238938762415
F7: 4,7                                  # 20 pairs
* PAIR I7: 4,7 ROW 7
F7: 4,7,2,8,9                            # reduction candidate for 4,7
F7: 2,8,9 => SOLVED
* 863579142197624853452813976529136784386497521741285369215348697674951238938762415
F7: 4,7                                  # 20 pairs
* PAIR I7: 4,7 COL I
I4: 4,7,3,8,9                            # reduction candidate for 4,7
I4: 4,7 => SOLVED
* 863579142197624853452813976529136784386497521741285369215348697674951238938762415
I4: 3,8,9                                # 16 pairs
I5: 4,7,1,9                              # reduction candidate for 4,7
I5: 4,7                                  # 16 pairs
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-065-base-pr-000.dot
* REASONING
* DIS # F7: 2,4 => CTR => F7: 7,8,9
* PRF # F5: 4,7 => SOL
* PRF # I5: 1,9 => SOL
* PRF # I4: 4,7 => SOL
* DIS # G8: 8 => CTR => G8: 2,3
* DIS # F7: 2,9 => CTR => F7: 4,7,8
* PRF # H7: 2,9 => SOL
* PRF # F7: 2,8,9 => SOL
* PRF # F7: 2,8,9 => SOL
* PRF # I4: 4,7 => SOL
* CNT  10 HDP CHAINS /  56 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A7,C4,D1,D3,D5,D9,E2,F2,G1,G2,G3,G4,G6,G9,I7)
* 863.7..421976.....452....7652.1.....38....5..74..8.....153..6...74.......38......
* PAIR D1: 5,9 BLK 2
F1: 5,9,1                                # reduction candidate for 5,9
F1: 5,9                                  # 16 pairs
F1: 1                                    # 16 pairs
* PAIR D1: 5,9 COL D
D6: 5,9,2                                # reduction candidate for 5,9
D6: 2                                    # 19 pairs
D6: 5,9                                  # 17 pairs
* PAIR E2: 2,4 COL E
E5: 2,4,6,9                              # reduction candidate for 2,4
E5: 2,4                                  # 21 pairs
E7: 2,4,9                                # reduction candidate for 2,4
E7: 2,4                                  # 17 pairs
* PAIR F2: 2,4 COL F
F5: 2,4,6,7,9                            # reduction candidate for 2,4
F5: 2,4                                  # 16 pairs
F7: 2,4,7,8,9                            # reduction candidate for 2,4
F7: 2,4 => CTR
* 863.7..421976..8..452....7652.1..7.838.4.75..74..8.....153..687.74.......387..4..
* RESTART
* PAIR F2: 2,4 COL F
F5: 2,4,6,7,9                            # reduction candidate for 2,4
F5: 2,4                                  # 16 pairs
F5: 6,7,9                                # 15 pairs
* PAIR RESTART
* PAIR F2: 2,4 COL F
F5: 2,4,6,7,9                            # reduction candidate for 2,4
F5: 2,4                                  # 16 pairs
F5: 6,7,9                                # 15 pairs
* PAIR D3: 8,9 BLK 2
F3: 8,9,1,3                              # reduction candidate for 8,9
F3: 8,9                                  # 16 pairs
F3: 1,3                                  # 16 pairs
* PAIR D3: 8,9 COL D
D8: 8,9,2                                # reduction candidate for 8,9
D8: 8,9                                  # 19 pairs
D8: 2                                    # 17 pairs
* PAIR G1: 1,9 ROW 1
F1: 1,9,5                                # reduction candidate for 1,9
F1: 1,9                                  # 16 pairs
F1: 5                                    # 15 pairs
* PAIR G2: 3,8 BLK 3
H2: 3,8,5                                # reduction candidate for 3,8
H2: 3,8                                  # 17 pairs
I2: 3,8,5                                # reduction candidate for 3,8
I2: 3,8                                  # 16 pairs
* PAIR G2: 3,8 COL G
G8: 3,8,2                                # reduction candidate for 3,8
G8: 2                                    # 19 pairs
G8: 3,8                                  # 17 pairs
* PAIR G3: 1,9 ROW 3
E3: 1,9,3                                # reduction candidate for 1,9
E3: 1,9                                  # 16 pairs
F3: 1,9,3,8                              # reduction candidate for 1,9
F3: 1,9                                  # 18 pairs
* PAIR C4: 6,9 BLK 4
C5: 6,9,1                                # reduction candidate for 6,9
C5: 6,9                                  # 17 pairs
C6: 6,9,1                                # reduction candidate for 6,9
C6: 6,9                                  # 16 pairs
* PAIR C4: 6,9 ROW 4
E4: 6,9,3,4                              # reduction candidate for 6,9
E4: 6,9                                  # 19 pairs
F4: 6,9,3,4,7                            # reduction candidate for 6,9
F4: 6,9                                  # 18 pairs
H4: 6,9,3,8                              # reduction candidate for 6,9
H4: 6,9                                  # 19 pairs
* PAIR D5: 4,7 BLK 5
F4: 4,7,3,6,9                            # reduction candidate for 4,7
F4: 4,7                                  # 17 pairs
F5: 4,7,2,6,9                            # reduction candidate for 4,7
F5: 4,7 => SOLVED
* 863579142197624853452813976529136784386497521741285369215348697674951238938762415
* DURATION: 0:00:30.032609  START: 04:53:43.859062  END: 04:54:13.891671 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-065-base-pr-001.dot
* REASONING
* DIS # F7: 2,4 => CTR => F7: 7,8,9
* PRF F7: 7,8,9 # F5: 4,7 => SOL
* STA F7: 7,8,9 + F5: 4,7
* CNT   2 HDP CHAINS /  31 HYP OPENED

Header Info

Top 500 Minimum 17 065

solution: 863579142197624853452813976529136784386497521741285369215348697674951238938762415
info: 1441     FNBTHWX  S8.f     5673

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

Solution

position: 863579142197624853452813976529136784386497521741285369215348697674951238938762415 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 # F1: 5,9 => UNS
* INC # F1: 1 => UNS
* INC # D6: 5,9 => UNS
* INC # D6: 2 => UNS
* INC # E5: 2,4 => UNS
* INC # E7: 2,4 => UNS
* INC # F5: 2,4 => UNS
* DIS # F7: 2,4 => CTR => F7: 7,8,9
* INC # F7: 7,8,9 => UNS
* INC # F3: 8,9 => UNS
* INC # F3: 1,3 => UNS
* INC # D8: 8,9 => UNS
* INC # D8: 2 => UNS
* INC # F1: 1,9 => UNS
* INC # F1: 5 => UNS
* INC # H2: 3,8 => UNS
* INC # I2: 3,8 => UNS
* INC # G8: 3,8 => UNS
* INC # G8: 2 => UNS
* INC # E3: 1,9 => UNS
* INC # F3: 1,9 => UNS
* INC # C5: 6,9 => UNS
* INC # C6: 6,9 => UNS
* INC # E4: 6,9 => UNS
* INC # F4: 6,9 => UNS
* INC # H4: 6,9 => UNS
* INC # F4: 4,7 => UNS
* PRF # F5: 4,7 => SOL
* INC # F5: 2,6,9 => UNS
* INC # I5: 4,7 => UNS
* PRF # I5: 1,9 => SOL
* PRF # I4: 4,7 => SOL
* INC # I4: 3,8,9 => UNS
* INC # I5: 4,7 => UNS
* INC # F4: 4,7 => UNS
* INC # F4: 3,6,9 => UNS
* INC # H6: 2,3 => UNS
* INC # H6: 1,6,9 => UNS
* INC # F6: 2,3 => UNS
* INC # F6: 5,6,9 => UNS
* INC # G8: 2,3 => UNS
* DIS # G8: 8 => CTR => G8: 2,3
* INC # A8: 2,9 => UNS
* INC # A9: 2,9 => UNS
* INC # E7: 2,9 => UNS
* DIS # F7: 2,9 => CTR => F7: 4,7,8
* INC # F7: 4,7,8 => UNS
* PRF # H7: 2,9 => SOL
* INC # H7: 8 => UNS
* INC # F7: 4,7 => UNS
* PRF # F7: 2,8,9 => SOL
* INC # F7: 4,7 => UNS
* PRF # F7: 2,8,9 => SOL
* PRF # I4: 4,7 => SOL
* INC # I4: 3,8,9 => UNS
* INC # I5: 4,7 => UNS
* CNT  56 HDP CHAINS /  56 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* INC # F1: 5,9 => UNS
* INC # F1: 1 => UNS
* INC # D6: 5,9 => UNS
* INC # D6: 2 => UNS
* INC # E5: 2,4 => UNS
* INC # E7: 2,4 => UNS
* INC # F5: 2,4 => UNS
* DIS # F7: 2,4 => CTR => F7: 7,8,9
* INC F7: 7,8,9 # F5: 2,4 => UNS
* INC F7: 7,8,9 # F5: 6,7,9 => UNS
* INC F7: 7,8,9 # F5: 2,4 => UNS
* INC F7: 7,8,9 # F5: 6,7,9 => UNS
* INC F7: 7,8,9 # F3: 8,9 => UNS
* INC F7: 7,8,9 # F3: 1,3 => UNS
* INC F7: 7,8,9 # D8: 8,9 => UNS
* INC F7: 7,8,9 # D8: 2 => UNS
* INC F7: 7,8,9 # F1: 1,9 => UNS
* INC F7: 7,8,9 # F1: 5 => UNS
* INC F7: 7,8,9 # H2: 3,8 => UNS
* INC F7: 7,8,9 # I2: 3,8 => UNS
* INC F7: 7,8,9 # G8: 3,8 => UNS
* INC F7: 7,8,9 # G8: 2 => UNS
* INC F7: 7,8,9 # E3: 1,9 => UNS
* INC F7: 7,8,9 # F3: 1,9 => UNS
* INC F7: 7,8,9 # C5: 6,9 => UNS
* INC F7: 7,8,9 # C6: 6,9 => UNS
* INC F7: 7,8,9 # E4: 6,9 => UNS
* INC F7: 7,8,9 # F4: 6,9 => UNS
* INC F7: 7,8,9 # H4: 6,9 => UNS
* INC F7: 7,8,9 # F4: 4,7 => UNS
* PRF F7: 7,8,9 # F5: 4,7 => SOL
* STA F7: 7,8,9 + F5: 4,7
* CNT  31 HDP CHAINS /  31 HYP OPENED