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Please explane solution and give name of technique.
Hints were used to validate earlier used techniques.
I'm having the idea i'm really close...
Any tips for in the future?
JC Van Hay wrote:1. Only eventual "~fish?" for the digits 7 and 8 => extremely easy puzzle
2. Incomplete application of the Sudoku Rule : a candidate is (placed/excluded) if it (belongs/doesn't belong) to all the solutions either of the same digit or of a unit.
2a. You exclude 8r8c5, but the solutions of the 8s exclude 8r8c5 and 8r7c89. Interpretation : Skyscraper(8C68)
2b. The solutions of C6 exclude (27)r7c6. Interpretation : NP(27)r39c6 or HP(58)r57c6
3. stte
+---------+---------+---------+
|-1 1 . | 1 1 . | . . . |
| 1 1 . | 1 . . | . . . |
| . . . | . . . | . . 1 |
+---------+---------+---------+
| 1 1 . | 1 1 . | . . . |
| 1 . . | 1 . . | . . . |
| . . . | . . . | . . 1 |
+---------+---------+---------+
| . . . | . . . | . . . |
| . . . | . . . | . . . |
| . . 1 | . . 1 | . . . |
+---------+---------+---------+
+---------+---------+---------+
|-1 1 . | 1 1 . | . . . |
| 1 1 . | 1 . . | . . . |
| . . . | . . . | . . 1 |
+---------+---------+---------+
| 1 1 . | . . . | 1 1 . |
| 1 . . | . . . | 1 . . |
| . . . | . . 1 | . . . |
+---------+---------+---------+
| . . . | 1 1 . | 1 1 . |
| . . . | 1 . . | 1 . . |
| . . 1 | . . . | . . . |
+---------+---------+---------+
*----------------------------------------------*
| 29 8 4 | 5 3 1 | 29 7 6 |
| 25 57 37 | 6 247 9 | 1 348 348 |
| 6 17 1379 | 8 247 #27 | 29 349 5 |
|--------------+----------------+--------------|
| 8 3 2 | 4 9 6 | 7 5 1 |
| 7 4 56 | 2 1 58 | 689 3689 389 |
| 1 9 56 | 7 58 3 | 4 68 2 |
|--------------+----------------+--------------|
| 4 2567 79 | 19 2578 x58-27 | 3 1689 789 |
| 59 1567 179 | 3 578 4 | 689 2 789 |
| 3 27 8 | 19 6 #27 | 5 149 49 |
*----------------------------------------------*
*--------------------------------------------*
| 29 8 4 | 5 3 1 | 29 7 6 |
| 25 57 37 | 6 247 9 | 1 348 348 |
| 6 17 1379 | 8 247 27 | 29 34 5 |
|--------------+-------------+---------------|
| 8 3 2 | 4 9 6 | 7 5 1 |
| 7 4 56 | 2 1 b58 |c68 39 39 |
| 1 9 56 | 7 58 3 | 4 68 2 |
|--------------+-------------+---------------|
| 4 2567 79 | 19 2578 a58 | 3 169-8 79-8 |
| 59 1567 179 | 3 57-8 4 |d68 2 789 |
| 3 27 8 | 19 6 27 | 5 149 49 |
*--------------------------------------------*
+---------+---------+---------+
|-1 1 . | 1 1 . | . . . |
| 1 1 . | 1 . . | . . . |
| . . . | . . . | . . 1 |
+---------+---------+---------+
| 1 1 . | 1 1 . | . . . |
| 1 . . | 1 . . | . . . |
| . . . | . . . | . . 1 |
+---------+---------+---------+
| . . . | . . . | . . . |
| . . . | . . . | . . . |
| . . 1 | . . 1 | . . . |
+---------+---------+---------+
+---------+---------+---------+
|-1 1 . | 1 1 . | . . . |
| 1 1 . | 1 . . | . . . |
| . . . | . . . | . . 1 |
+---------+---------+---------+
| 1 1 . | . . . | 1 1 . |
| 1 . . | . . . | 1 . . |
| . . . | . . 1 | . . . |
+---------+---------+---------+
| . . . | 1 1 . | 1 1 . |
| . . . | 1 . . | 1 . . |
| . . 1 | . . . | . . . |
+---------+---------+---------+
In such a case, it becomes necessary to determine the common exclusions associated with each set of solutions of the digit from each candidate of a simple constraint (for example : a bilocal, most of the time, or a trilocal covering 2 or 3 boxes). Note however, that a complete and detailed enumeration of the solutions of the digit is not required if the Keith's principle is taken into account during the process. For completeness, it remains then to justify each exclusion by the solutions of the least number of constraints for the digit.
Furthermore, in a solution of the puzzle, the sudoku rule imply that each unit contains a permutation of the 9 digits.
Except for the hidden pairs and obvious ones, the other eventual naked and hidden subsets are easily found by inspection of the 27 units once all the candidates are determined.
Leren wrote:The puzzle in line format : ...6..9.2..1..8....6.7.4...73.4..29.....1.....18..9.35...1.2.4....9..6..5.7..6...
The cells marked a-b-c-d form a Skyscraper. If you are unfamiliar with this move here is a simple explanation:
Sudoku1234567 wrote : What is this line format? Is this notation used for a technique?
+---------+---------+---------+
|-1 1 . | 1 a1 . | . . . |
| 1 1 . | 1 . . | . . . |
| . . . | . . . | . . 1 |
+---------+---------+---------+
|c1 c1 . | 1 b1 . | . . . |
|d1 . . | 1 . . | . . . |
| . . . | . . . | . . 1 |
+---------+---------+---------+
| . . . | . . . | . . . |
| . . . | . . . | . . . |
| . . 1 | . . 1 | . . . |
+---------+---------+---------+
+---------+---------+---------+
|-1 1 . | 1 a1 . | . . . |
| 1 1 . | 1 . . | . . . |
| . . . | . . . | . . 1 |
+---------+---------+---------+
|g1 g1 . | . . . |e1 f1 . |
|h1 . . | . . . |e1 . . |
| . . . | . . 1 | . . . |
+---------+---------+---------+
| . . . | 1 b1 . |c1 c1 . |
| . . . | 1 . . |d1 . . |
| . . 1 | . . . | . . . |
+---------+---------+---------+