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very extreme puzzle

 
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Ajò Dimonios



Joined: 01 May 2017
Posts: 339
Location: Sassari Italy

PostPosted: Wed May 10, 2017 11:16 pm    Post subject: very extreme puzzle Reply with quote

Code:

+---------------------+-----------------+--------------------+
| 2358   589    6     | 458  7    138   | 1349  12359  12459 |
| 357    1      359   | 2    345  36    | 34679 35679  8     |
| 4      578    2358  | 568  1358 9     | 1367  123567 12567 |
+---------------------+-----------------+--------------------+
| 5678   456789 4589  | 1    489  678   | 2     5679   3     |
| 1267   3      1249  | 4679 249  5     | 8     1679   1679  |
| 125678 56789  12589 | 6789 2389 23678 | 1679  4      15679 |
+---------------------+-----------------+--------------------+
| 9      568    1358  | 578  1258 4     | 1367  123678 1267  |
| 168    2      148   | 3    189  178   | 5     16789  14679 |
| 1358   458    7     | 589  6    128   | 1349  12389  1249  |
+---------------------+-----------------+--------------------+
It takes more days to solve it
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Ajò Dimonios



Joined: 01 May 2017
Posts: 339
Location: Sassari Italy

PostPosted: Thu May 11, 2017 12:14 pm    Post subject: Reply with quote

Code:

+-----------------+---------------+------------------+
| 2358 589   6    | 458  7    138 | 1349 1235  12459 |
| 357  1     359  | 2    345  36  | 4679 35679 8     |
| 4    578   2358 | 568  1358 9   | 1367 1235  12567 |
+-----------------+---------------+------------------+
| 5678 4679  4589 | 1    489  678 | 2    5679  3     |
| 1267 3     1249 | 4679 249  5   | 8    1679  679   |
| 1258 56789 1258 | 6789 238  238 | 1679 4     15679 |
+-----------------+---------------+------------------+
| 9    568   1358 | 578  1258 4   | 1367 1238  1267  |
| 168  2     148  | 3    189  178 | 5    16789 4679  |
| 1358 458   7    | 589  6    128 | 1349 1238  1249  |
+-----------------+---------------+------------------+
As a first step you can use the multifish technique.
Multi-Fish pattern with base set of 4,6,7 and 9
16 Truths = {4679R2, 4679R4, 4679R5, 4679R8}
16 Links = {67c1, 49c3, 49c5, 67c6, 679c8, R2C7, R4C2, R5C4, R5C9, R8C9}
17 Eliminations: R2C7<>3, R4C2<>5, R4C2<>8, R5C9<>1, R8C9<>1, R1C8<>9, R3C8<>6, R3C8<>7, R6C1<>6, R6C1<>7, R6C3<>9, R6R5<>9, R6C6<>6, R6C6<>7, R7C8<>6, R7C8<>7, R9C8<>9

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Ajò Dimonios



Joined: 01 May 2017
Posts: 339
Location: Sassari Italy

PostPosted: Fri May 12, 2017 11:32 am    Post subject: Reply with quote

Code:

+----------------+--------------+-----------------+
| 2358 589  6    | 4   7    138 | 139  1235 1259  |
| 357  1    359  | 2   35   6   | 4    79   8     |
| 4    578  235  | 58  1358 9   | 1367 1235 12567 |
+----------------+--------------+-----------------+
| 5678 4679 4589 | 1   489  78  | 2    5679 3     |
| 1267 3    1249 | 679 249  5   | 8    1679 679   |
| 1258 679  1258 | 679 238  23  | 1679 4    15679 |
+----------------+--------------+-----------------+
| 9    68   1358 | 578 1258 4   | 1367 1238 1267  |
| 168  2    148  | 3   189  178 | 5    679  4679  |
| 1358 458  7    | 589 6    128 | 139  1238 1249  |
+----------------+--------------+-----------------+
Multi-Fish pattern with base set of 4,6,7 and 9
19 Truths = {4679R1, 4679R3, 4679R4, 679R5, 4679R7}
19 Links = {67c0, 49c2, 49c4, 67c5, 1n6, 1n7, 3n1, 4n3, 5n1, 5n3, 7n7, 7n8, 679b6}
7 Eliminations: R2C8<>3, R2C8<>5,R6C2<>5,R6C2<>8, R6C4<>8, R8C8<>1,R8C8<>8

If 5 is true in r7c2 then the 8 at r1c2 is both true and false, hence 5 is false and can be eliminated

If 6 is true in r2c7 then the 1 at r7c9 is both true and false, hence 6 is false and can be eliminated

If 3 is true in r2c6 then the 4 at r1c9 is both true and false, hence 3 is false and can be eliminated

If 4 is false in r1c4 then the 6 at r6c4 is both true and false, hence 4 must be true in r1c4
Finned swordfish of 8s at r1c2, r3c2, r3c4, r7c2, r7c4, r7c8, r9c2, r9c4, r9c8 eliminating 8 from r3c3

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JC Van Hay



Joined: 13 Jun 2010
Posts: 494
Location: Charleroi, Belgium

PostPosted: Fri May 12, 2017 6:06 pm    Post subject: Reply with quote

Code:
+------------------------+---------------------+------------------------+
| 2358    (589)    6     | (458)  7      138   | 1349    12359   12459  |
| (357)   1        (359) | 2      (345)  (36)  | 4679-3  679-35  8      |
| 4       (578)    2358  | (568)  1358   9     | 1367    123567  12567  |
+------------------------+---------------------+------------------------+
| 5678    4679-58  4589  | 1      489    678   | 2       5679    3      |
| 1267    3        1249  | 4679   249    5     | 8       1679    1679   |
| 125678  679-58   12589 | 679-8  2389   23678 | 1679    4       15679  |
+------------------------+---------------------+------------------------+
| 9       (568)    1358  | (578)  1258   4     | 1367    123678  1267   |
| (168)   2        (148) | 3      (189)  (178) | 5       679-18  4679-1 |
| 1358    (458)    7     | (589)  6      128   | 1349    12389   1249   |
+------------------------+---------------------+------------------------+
Continuous All Cell Loop :
The set P={R1379C24, R28C1345} of 16 cells is a proper subset of
the set C={(58)C24, (35)R2, (18)R8, (46)B27, (78)B18} of 16 constraints.
Therefore, the set C-P={(58)r46c2, 8r6c4, 3r2c78, 5r2c8, 1r8c89, 8r8c8} of 11 candidates is excluded.

Note :
r13c2=79 -> r2c56=46 -> r78c4=79 -> r8c13=64 -> r13c2=79
r2c13=79 -> r79c2=46 -> r8c56=79 -> r13c4=46 -> r2c13=79

Solving P :
1. 7r3c2 + 9r1c2 -> 0 solution [r6c24=6!?]
2. 7r2c1 + 9r2c3 -> 0 solution [r28c8=6!?]
3a. 7r3c2 + 9r2c3 + 4r2c5 -> 0 solution
3b. 7r3c2 + 9r2c3 + 4r1c4 + 4r9c2 -> 0 solution
3c. 7r3c2 + 9r2c3 + 4r1c4 + 4r8c3 -> 0 solution via HP(23)r6c56, LC{8B5}, NP(69)r48c8 and Swordfish{8R18C4}
4a. 7r2c1 + 9r1c2 + 4r2c5 + 4r9c2 -> 0 solution
4b. 7r2c1 + 9r1c2 + 4r2c5 + 4r8c3 -> 0 solution
4c. 7r2c1 + 9r1c2 + 4r1c4 + 4r9c2 -> 0 solution
4d. 7r2c1 + 9r1c2 + 4r1c4 + 4r8c3 + 7r8c6 -> 0 solution
4e. 7r2c1 + 9r1c2 + 4r1c4 + 4r8c3 + 7r7c4 -> 1 solution via XWing{3C37}
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Ajò Dimonios



Joined: 01 May 2017
Posts: 339
Location: Sassari Italy

PostPosted: Fri May 12, 2017 10:36 pm    Post subject: Reply with quote

I continue from my previous post
If R1C1=3 produces contradiction two 1 in column7 then R1C1<>3
If R9C4=5 produces contradiction R7C5 empty then R9C4<>5
If R7C2=8 produces contradiction R1C7 empty then R7C2<>8
If R7C3=8 produces contradiction R1C9 empty then R7C3<>8
If R8C1=1 produces contradiction R3C3 empty then R8C1<>1
If R8C5=1 produces contradiction R5C3 empty then R8C5<>1
solution with basic strategies
Code:

+---------------+--------------+-----------------+
| 25   589 6    | 4   7    138 | 139  1235 1259  |
| 357  1   359  | 2   35   6   | 4    79   8     |
| 4    578 235  | 58  1358 9   | 1367 1235 12567 |
+---------------+--------------+-----------------+
| 567  479 4589 | 1   48   78  | 2    5679 3     |
| 1267 3   1249 | 679 24   5   | 8    1679 679   |
| 125  79  1258 | 679 238  238 | 1679 4    15679 |
+---------------+--------------+-----------------+
| 9    6   135  | 578 1258 4   | 137  1238 127   |
| 8    2   14   | 3   9    17  | 5    67   467   |
| 135  45  7    | 8   6    128 | 139  1238 1249  |
+---------------+--------------+-----------------+

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