find the first single

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find the first single

Postby urhegyi » Mon Jul 05, 2021 8:35 am

In this example you have to find the first single by sudoku techniques and then it's completely solved by singles till the end.
Image
Code: Select all
....6...2.1..7..4.6..3.2.....8.......6..1..5.3..6....97....4....5..8..7.9.....4.3
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Re: find the first single

Postby Leren » Mon Jul 05, 2021 9:39 am

Code: Select all
*-------------------------------------------------------*
| 458 3479 4579  | 14589 6     1589 | 579    39    2    |
| 258 1    2359  | 589   7     589  | 3569   4     56   |
| 6   479  4579  | 3     459   2    | 15789  189   1578 |
|----------------+------------------+-------------------|
| 15  2479 8     | 24579 23459 579  | 1267   1236  1467 |
| 24  6    2479  | 24789 1     3789 | 2378   5     478  |
| 3   247  15    | 6     245   578  | 1278   128   9    |
|----------------+------------------+-------------------|
| 7   238  126   | 129   239   4    | 125689 12689 1568 |
| 124 5    12346 | 129   8     1369 | 1269   7     1-6  |
| 9   28   126   | 1257  25    1567 | 4      1268  3    |
*-------------------------------------------------------*

Kraken Column 4 Digit 5:   

6 r8c9 - 6r2c9 = (6-3) r2c7 = (3-2) r2c3 = 2r2c1 - (2=4) r5c1 - 4r6c2 = 4r6c5 - 4r3c5 = 4r1c4 - 5 r1c4;

6 r8c9 - (6=5) r2c9                                                                           - 5 r2c4;

6 r8c9 - (6=5) r2c9                                       - 5 r2c1;

6 r8c9 - 6r2c9 = (6-3) r2c7 = (3-2) r2c3 = (2-8) r2c1 = (8-5) r1c1 *= 5r4c1                   - 5 r4c4

6 r8c9 - 6r8c6 = (6-7)r9c6 = 7 r9c4                                                           - 5 r9c4; => - 6 r8c9; btte
Leren
 
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Re: find the first single

Postby denis_berthier » Tue Jul 06, 2021 4:28 am

.
FORCING-T&E(W1) applied to bivalue candidates n2r5c1 and n4r5c1 :
===> 21 values decided in both cases: n1r4c1 n5r6c3 n6r2c9 n1r8c9 n2r4c4 n9r8c4 n1r7c4 n6r7c3 n1r9c3 n5r7c9 n8r9c2 n4r6c5 n7r6c2 n8r6c6 n8r2c4 n5r2c1 n8r1c1 n4r1c4 n5r1c7 n1r1c6 n5r4c6
===> 123 candidates eliminated in both cases: n4r1c1 n5r1c1 n4r1c2 n7r1c2 n9r1c2 n3r1c3 n4r1c3 n5r1c3 n1r1c4 n5r1c4 n8r1c4 n9r1c4 n5r1c6 n8r1c6 n9r1c6 n3r1c7 n7r1c7 n9r1c7 n2r2c1 n8r2c1 n5r2c3 n9r2c3 n5r2c4 n9r2c4 n5r2c6 n8r2c6 n5r2c7 n6r2c7 n5r2c9 n7r3c2 n5r3c3 n9r3c3 n4r3c5 n5r3c7 n8r3c7 n9r3c7 n9r3c8 n1r3c9 n5r3c9 n7r3c9 n2r4c1 n4r4c1 n5r4c1 n2r4c2 n7r4c2 n4r4c4 n5r4c4 n7r4c4 n9r4c4 n2r4c5 n4r4c5 n5r4c5 n3r4c6 n7r4c6 n9r4c6 n1r4c7 n2r4c7 n3r4c7 n1r4c8 n2r4c8 n1r4c9 n6r4c9 n4r5c3 n7r5c3 n2r5c4 n4r5c4 n8r5c4 n9r5c4 n7r5c6 n8r5c6 n2r5c7 n7r5c7 n7r5c9 n2r6c2 n4r6c2 n1r6c3 n2r6c3 n4r6c3 n7r6c3 n2r6c5 n5r6c5 n5r6c6 n7r6c6 n7r6c7 n8r6c7 n8r6c8 n8r7c2 n1r7c3 n2r7c3 n3r7c3 n2r7c4 n9r7c4 n9r7c5 n1r7c7 n2r7c7 n5r7c7 n6r7c7 n1r7c8 n2r7c8 n6r7c8 n1r7c9 n6r7c9 n8r7c9 n1r8c1 n1r8c3 n2r8c3 n6r8c3 n1r8c4 n2r8c4 n1r8c6 n9r8c6 n1r8c7 n9r8c7 n6r8c9 n2r9c2 n2r9c3 n6r9c3 n1r9c4 n2r9c4 n1r9c6 n5r9c6 n1r9c8 n8r9c8

Code: Select all
CURRENT RESOLUTION STATE:
   8         3         79        4         6         1         5         39        2         
   5         1         23        8         7         9         39        4         6         
   6         49        47        3         59        2         17        18        8         
   1         49        8         2         39        5         67        36        47       
   24        6         29        7         1         39        38        5         48       
   3         7         5         6         4         8         12        12        9         
   7         23        6         1         23        4         89        89        5         
   24        5         34        9         8         36        26        7         1         
   9         8         1         57        25        67        4         26        3

stte
denis_berthier
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Re: find the first single

Postby jco » Tue Jul 06, 2021 12:52 pm

Code: Select all
.-------------------------------------------------------------.
| 458  3479  34579 | 14589  6      1589 | 3579    39     2    |
|e258  1    f2359  |v589    7     v589  |f3569    4    wf56   |
| 6    479   4579  | 3   uAa459    2    | 15789   189    1578 |
|------------------+--------------------+---------------------|
| 15   2479  8     | 24579  23459  3579 | 12367   1236   1467 |
|d24   6     2479  | 24789  1      3789 | 2378    5      478  |
| 3   c247   15    | 6     b245    578  | 1278    128    9    |
|------------------+--------------------+---------------------|
| 7    238   1236  |C129   C239    4    | 125689  12689  1568 |
|F24-1 5    E12346 |C129    8     D1369 | 1269    7    wg16   |
| 9    28    126   | 1257  B25     1567 | 4       1268   3    |
'-------------------------------------------------------------'

Kraken Cell (459)r3c5 => -1 r8c1; lclste
(4)r3c5 - r6c5 = r6c2 - (4=2)r4c1 - r2c1 = (236)r2c379 - (6=1)r8c9
(5)r3c5 - (5=2)r9c5 - (2=193)b8p124 - r8c6 = (3-4)r8c3 = (4)r8c1
(9)r3c5 - (9=58)r2c46 - (5=61)r28c9
JCO
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