Medium Sandwich Sudoku
Ready to sharpen your skills? Medium Sandwich Sudoku puzzles introduce interactions between the variant constraint and classic Sudoku techniques. You'll need to combine both skill sets to progress.
What to expect at Medium level
Medium Sandwich Sudoku puzzles require you to combine the variant constraint with standard Sudoku deduction - Naked pairs, hidden singles, and unit scans. The constraint is more tightly woven into the grid, so you'll need to think a few steps ahead.
Best suited for players comfortable with Easy Sandwich Sudoku who want to build their pattern recognition.
Difficulty overview
About Sandwich Sudoku
Sandwich Sudoku places clues along the outside of the grid. Each clue gives the sum of all digits squeezed between the 1 and the 9 in that row or column. The positions of 1 and 9 vary, so the 'sandwich' can have 0 to 7 cells depending on where they land. A clue of 0 means 1 and 9 are adjacent. A clue of 35 means all digits 2–8 are between them.
Solving Techniques for Medium Level
| Technique | Description | Level |
|---|---|---|
| Clue 0 Means Adjacent 1 and 9 | A sandwich clue of 0 means 1 and 9 are side-by-side with nothing between them. Place this pair immediately. | Beginner |
| Clue 35 Means 1 and 9 at Ends | A clue of 35 = 2+3+4+5+6+7+8. All middle digits are sandwiched, placing 1 and 9 at the two ends of the row/column. | Beginner |
| Position Enumeration | For each clue, enumerate all valid positions of 1 and 9 such that the enclosed digits sum to the clue. Cross-reference with column clues. | Intermediate |
| Digit Forcing from Both Sides | Use clues from both the row and column sides to triangulate the positions of 1 and 9 simultaneously. | Intermediate |
Master these, then take on Hard Killer Sudoku to learn Advanced techniques.