Analysis of xx-top500-014-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: ....85...9.....3......4.....81....4....2...7.........82..9..6........5.3.4....... initial

Autosolve

position: ....854699547..3818...49752.8159.2464..2.8.75...4...382.895.614...8.45.3.4.6..8.7 autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* DIS # B1: 1,3 => CTR => B1: 2,7
* DIS # E6: 1,6 => CTR => E6: 7
* DIS # E9: 1,2 => CTR => E9: 3
* CNT   3 HDP CHAINS /  19 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 # B1: 1,3 => CTR => B1: 2,7
* DIS B1: 2,7 # A1: 7 => CTR => A1: 1,3
* DIS B1: 2,7 + A1: 1,3 # E6: 1,6 => CTR => E6: 7
* PRF B1: 2,7 + A1: 1,3 + E6: 7 # B6: 6,9 => SOL
* STA B1: 2,7 + A1: 1,3 + E6: 7 + B6: 6,9
* CNT   4 HDP CHAINS /  13 HYP OPENED

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

Details

Positions

....85...9.....3......4.....81....4....2...7.........82..9..6........5.3.4....... initial
....854699547..3818...49752.8159.2464..2.8.75...4...382.895.614...8.45.3.4.6..8.7 autosolve
327185469954726381816349752781593246493268175562471938238957614679814523145632897 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (15)
C3: 3,6
D1: 1,3
E2: 2,6
F2: 2,6
D3: 1,3
A4: 3,7
F4: 3,7
F6: 1,6
G5: 1,9
G6: 1,9
B7: 3,7
F7: 3,7
F9: 1,2
H8: 2,9
H9: 2,9

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
D1,D3: 1.. / D1 = 1  => 18 pairs (_) / D3 = 1  => 16 pairs (_)
G5,G6: 1.. / G5 = 1  => 14 pairs (_) / G6 = 1  =>  0 pairs (X)
B3,D3: 1.. / B3 = 1  => 18 pairs (_) / D3 = 1  => 16 pairs (_)
E5,G5: 1.. / E5 = 1  =>  0 pairs (X) / G5 = 1  => 14 pairs (_)
F6,F9: 1.. / F6 = 1  => 12 pairs (_) / F9 = 1  => 23 pairs (_)
B1,C1: 2.. / B1 = 2  => 17 pairs (_) / C1 = 2  => 15 pairs (_)
E2,F2: 2.. / E2 = 2  => 12 pairs (_) / F2 = 2  => 23 pairs (_)
B6,C6: 2.. / B6 = 2  => 15 pairs (_) / C6 = 2  => 17 pairs (_)
H8,H9: 2.. / H8 = 2  => 15 pairs (_) / H9 = 2  =>  0 pairs (X)
E8,H8: 2.. / E8 = 2  =>  0 pairs (X) / H8 = 2  => 15 pairs (_)
B1,B6: 2.. / B1 = 2  => 17 pairs (_) / B6 = 2  => 15 pairs (_)
C1,C6: 2.. / C1 = 2  => 15 pairs (_) / C6 = 2  => 17 pairs (_)
F2,F9: 2.. / F2 = 2  => 23 pairs (_) / F9 = 2  => 12 pairs (_)
D1,D3: 3.. / D1 = 3  => 16 pairs (_) / D3 = 3  => 18 pairs (_)
F4,E5: 3.. / F4 = 3  => 18 pairs (_) / E5 = 3  =>  0 pairs (X)
F7,E9: 3.. / F7 = 3  =>  0 pairs (X) / E9 = 3  => 18 pairs (_)
A4,F4: 3.. / A4 = 3  =>  0 pairs (X) / F4 = 3  => 18 pairs (_)
B7,F7: 3.. / B7 = 3  => 18 pairs (_) / F7 = 3  =>  0 pairs (X)
E5,E9: 3.. / E5 = 3  =>  0 pairs (X) / E9 = 3  => 18 pairs (_)
F4,F7: 3.. / F4 = 3  => 18 pairs (_) / F7 = 3  =>  0 pairs (X)
A6,C6: 5.. / A6 = 5  => 16 pairs (_) / C6 = 5  =>  0 pairs (X)
A9,C9: 5.. / A9 = 5  =>  0 pairs (X) / C9 = 5  => 16 pairs (_)
A6,A9: 5.. / A6 = 5  => 16 pairs (_) / A9 = 5  =>  0 pairs (X)
C6,C9: 5.. / C6 = 5  =>  0 pairs (X) / C9 = 5  => 16 pairs (_)
B3,C3: 6.. / B3 = 6  => 17 pairs (_) / C3 = 6  => 17 pairs (_)
E2,F2: 6.. / E2 = 6  => 23 pairs (_) / F2 = 6  => 12 pairs (_)
A6,A8: 6.. / A6 = 6  =>  0 pairs (X) / A8 = 6  => 17 pairs (_)
F2,F6: 6.. / F2 = 6  => 12 pairs (_) / F6 = 6  => 23 pairs (_)
F4,E6: 7.. / F4 = 7  =>  0 pairs (X) / E6 = 7  => 18 pairs (_)
F7,E8: 7.. / F7 = 7  => 18 pairs (_) / E8 = 7  =>  0 pairs (X)
A4,F4: 7.. / A4 = 7  => 18 pairs (_) / F4 = 7  =>  0 pairs (X)
B7,F7: 7.. / B7 = 7  =>  0 pairs (X) / F7 = 7  => 18 pairs (_)
E6,E8: 7.. / E6 = 7  => 18 pairs (_) / E8 = 7  =>  0 pairs (X)
F4,F7: 7.. / F4 = 7  =>  0 pairs (X) / F7 = 7  => 18 pairs (_)
G5,G6: 9.. / G5 = 9  =>  0 pairs (X) / G6 = 9  => 14 pairs (_)
H8,H9: 9.. / H8 = 9  =>  0 pairs (X) / H9 = 9  => 15 pairs (_)
C9,H9: 9.. / C9 = 9  =>  0 pairs (X) / H9 = 9  => 15 pairs (_)
* DURATION: 0:01:03.261360  START: 03:04:06.440776  END: 03:05:09.702136 2017-05-04
* CP COUNT: (37)
* CLUE FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A4,B7,C3,D1,D3,E2,F2,F4,F6,F7,F9,G5,G6,H8,H9)
* ....854699547..3818...49752.8159.2464..2.8.75...4...382.895.614...8.45.3.4.6..8.7
* PAIR C3: 3,6 BLK 1
B3: 3,6,1                                # reduction candidate for 3,6
B3: 1                                    # 18 pairs
B3: 3,6                                  # 16 pairs
* PAIR C3: 3,6 COL C
C5: 3,6,9                                # reduction candidate for 3,6
C5: 9                                    # 20 pairs
C5: 3,6                                  # 19 pairs
* PAIR D1: 1,3 ROW 1
A1: 1,3,7                                # reduction candidate for 1,3
A1: 1,3                                  # 18 pairs
B1: 1,3,2,7                              # reduction candidate for 1,3
B1: 1,3 => CTR
* 7.2.854699547..3818...497523815972464..238175.274..93827895.614...8.45.3.4.6..8.7
B1: 2,7                                  # 16 pairs
* PAIR D3: 1,3 ROW 3
B3: 1,3,6                                # reduction candidate for 1,3
B3: 6                                    # 17 pairs
B3: 1,3                                  # 17 pairs
* PAIR A4: 3,7 COL A
A1: 3,7,1                                # reduction candidate for 3,7
A1: 1                                    # 23 pairs
A1: 3,7                                  # 19 pairs
* PAIR F6: 1,6 BLK 5
E5: 1,6,3                                # reduction candidate for 1,6
E5: 1,6                                  # 18 pairs
E6: 1,6,7                                # reduction candidate for 1,6
E6: 1,6 => CTR
* ....854699547..3818.6.49752381597246469238175...4..938278953614...874523.436..897
E6: 7                                    # 18 pairs
* PAIR B7: 3,7 COL B
B1: 3,7,1,2                              # reduction candidate for 3,7
B1: 3,7                                  # 18 pairs
B1: 1,2                                  # 16 pairs
* PAIR F9: 1,2 BLK 8
E8: 1,2,7                                # reduction candidate for 1,2
E8: 1,2                                  # 18 pairs
E9: 1,2,3                                # reduction candidate for 1,2
E9: 1,2 => CTR
* ....854699547..3818.6.49752381597246469238175...4..938278953614...874523.436..897
E9: 3                                    # 18 pairs
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-014-base-pr-000.dot
* REASONING
* DIS # B1: 1,3 => CTR => B1: 2,7
* DIS # E6: 1,6 => CTR => E6: 7
* DIS # E9: 1,2 => CTR => E9: 3
* CNT   3 HDP CHAINS /  19 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A4,B7,C3,D1,D3,E2,F2,F4,F6,F7,F9,G5,G6,H8,H9)
* ....854699547..3818...49752.8159.2464..2.8.75...4...382.895.614...8.45.3.4.6..8.7
* PAIR C3: 3,6 BLK 1
B3: 3,6,1                                # reduction candidate for 3,6
B3: 1                                    # 18 pairs
B3: 3,6                                  # 16 pairs
* PAIR C3: 3,6 COL C
C5: 3,6,9                                # reduction candidate for 3,6
C5: 9                                    # 20 pairs
C5: 3,6                                  # 19 pairs
* PAIR D1: 1,3 ROW 1
A1: 1,3,7                                # reduction candidate for 1,3
A1: 1,3                                  # 18 pairs
B1: 1,3,2,7                              # reduction candidate for 1,3
B1: 1,3 => CTR
* 7.2.854699547..3818...497523815972464..238175.274..93827895.614...8.45.3.4.6..8.7
* RESTART
* PAIR D1: 1,3 ROW 1
A1: 1,3,7                                # reduction candidate for 1,3
A1: 7 => CTR
* 7231854699547..3818163497523815972464.9238175..24..9382.895.614...8.45.3.4.6..8.7
* PAIR RESTART
* PAIR D3: 1,3 ROW 3
B3: 1,3,6                                # reduction candidate for 1,3
B3: 6                                    # 23 pairs
B3: 1,3                                  # 20 pairs
* PAIR F6: 1,6 BLK 5
E5: 1,6,3                                # reduction candidate for 1,6
E5: 1,6                                  # 18 pairs
E6: 1,6,7                                # reduction candidate for 1,6
E6: 1,6 => CTR
* .27.854699547..38183614975238159724646.238175...4..938278953614...874523.4.6..897
* RESTART

* LEVEL 0 PASS 1 ROUND 2 (AUTO SOLVE) (A6,A8,A9,B1,B5,C1,C8,C9,E2,E5,E8,F2,F6,F9,G5,G6,H8,H9)
* 3..1854699547..3818163497527815932464.32.8.75...47..38238957614...8.45.3.4.63.8.7
* PAIR B5: 6,9 BLK 4
B6: 6,9,2                                # reduction candidate for 6,9
B6: 6,9 => SOLVED
* 327185469954726381816349752781593246493268175562471938238957614679814523145632897
* DURATION: 0:00:13.845308  START: 03:05:27.718802  END: 03:05:41.564110 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-014-base-pr-001.dot
* REASONING
* DIS # B1: 1,3 => CTR => B1: 2,7
* DIS B1: 2,7 # A1: 7 => CTR => A1: 1,3
* DIS B1: 2,7 + A1: 1,3 # E6: 1,6 => CTR => E6: 7
* PRF B1: 2,7 + A1: 1,3 + E6: 7 # B6: 6,9 => SOL
* STA B1: 2,7 + A1: 1,3 + E6: 7 + B6: 6,9
* CNT   4 HDP CHAINS /  13 HYP OPENED

Header Info

Top 500 Minimum 17 014

solution: 327185469954726381816349752781593246493268175562471938238957614679814523145632897
info: 1310     FNBTWXY  S8.f     6482

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

Solution

position: 327185469954726381816349752781593246493268175562471938238957614679814523145632897 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 # B3: 3,6 => UNS
* INC # B3: 1 => UNS
* INC # C5: 3,6 => UNS
* INC # C5: 9 => UNS
* INC # A1: 1,3 => UNS
* DIS # B1: 1,3 => CTR => B1: 2,7
* INC # B1: 2,7 => UNS
* INC # B3: 1,3 => UNS
* INC # B3: 6 => UNS
* INC # A1: 3,7 => UNS
* INC # A1: 1 => UNS
* INC # E5: 1,6 => UNS
* DIS # E6: 1,6 => CTR => E6: 7
* INC # E6: 7 => UNS
* INC # B1: 3,7 => UNS
* INC # B1: 1,2 => UNS
* INC # E8: 1,2 => UNS
* DIS # E9: 1,2 => CTR => E9: 3
* INC # E9: 3 => UNS
* CNT  19 HDP CHAINS /  19 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* INC # B3: 3,6 => UNS
* INC # B3: 1 => UNS
* INC # C5: 3,6 => UNS
* INC # C5: 9 => UNS
* INC # A1: 1,3 => UNS
* DIS # B1: 1,3 => CTR => B1: 2,7
* INC B1: 2,7 # A1: 1,3 => UNS
* DIS B1: 2,7 # A1: 7 => CTR => A1: 1,3
* INC B1: 2,7 + A1: 1,3 # B3: 1,3 => UNS
* INC B1: 2,7 + A1: 1,3 # B3: 6 => UNS
* INC B1: 2,7 + A1: 1,3 # E5: 1,6 => UNS
* DIS B1: 2,7 + A1: 1,3 # E6: 1,6 => CTR => E6: 7
* PRF B1: 2,7 + A1: 1,3 + E6: 7 # B6: 6,9 => SOL
* STA B1: 2,7 + A1: 1,3 + E6: 7 + B6: 6,9
* CNT  13 HDP CHAINS /  13 HYP OPENED