|
|
Posts: 1869
   
Location: India | Here is one cool way to solve the Number Pyramid, assuming that the puzzle is unique.
First the puzzle, with some naming convention | Then some easy filling starting with R6, then R5, then R4, then R3, then R2 | Now again starting with R5, R4, R3, R2 - there are only 2 possibilities for all cells. | Now lets wait and look at Row3 first cell. If the value is 8, in Row2 first cell it can be 7 or 9. Then Row2 can't be solved uniquely. | That means the first cell in Row2 has to be 4. That gives us a good lead, and lot can be solved further. | After that there are lot of 3s and 6s and 9 in remaining cells. Keeping that in mind, the puzzle can be solved easily.For example, in the bottom row 6 can't appear anywhere other than last 2 cells. | We can also do Odd Even Marking in each cell. | Further Odd Even marking. | Now the right cell in bottom row has to be Even, because the 2nd right has to be odd. | Since R7 cell2 can't be 6, R7 first cell can't be 3. So it has to be 1 (because numbers greater than 4 can't have same number next to it in a row)
 |
|
| |
|
PR 2020 (Casual and Word) Author
Posts: 349
Location: India | Great explanation Deb.
But I think new comers need to be a little careful while using the Uniqueness rule, it could backfire in many puzzles if used incorrectly.
I have seen people using Unique Rectangles in a Diagonal Sudoku with one of the corners of the rectangle lying on the diagonal.
Also seen puzzle creators using uniqueness while creating a puzzle, before proving that the puzzle has a unique solution.
|
| |
|
Posts: 1869
Location: India | Amit, agreed, players have to be careful while applying Uniqueness, though it provides shortcuts in many puzzles.
Also, this is not the only logical way to solve the puzzle. But i feel this is the quickest.
If other players have applied some other techniques, request them to post it here.
|
| |
|
WSPC Organizer
Posts: 542
Location: India | Thanks Deb for this great explanation. I have applied the uniqueness funda to solve this puzzle during test, but this even odd funda for new to me. Thanks again for putting this method. |
| |
WSPC 2017 • Schedule • Participation • Location • WSC • WPC • Contact •Search •Recent
Solving Number Pyramid in EG2 using Uniqueness funda
