Beginner Techniques - Eliminating Candidates in Sudoku
Solving Cells with Elimination
New to Sudoku? Learn how to play with an interactive puzzle in the how to play guide 🔗
Cell: A single square in the grid.
House: A 3x3 group of cells. In Not Evil Sudoku, the houses are grouped together and you can see them clearly below. There are a total of 9 houses in a 9x9 grid.
Candidates: The possible numbers that can go in a cell. Since every sudoku cell has to be a number from 1-9, the candidates for a cell are some subset of 1-9.
House: A 3x3 group of cells. In Not Evil Sudoku, the houses are grouped together and you can see them clearly below. There are a total of 9 houses in a 9x9 grid.
Candidates: The possible numbers that can go in a cell. Since every sudoku cell has to be a number from 1-9, the candidates for a cell are some subset of 1-9.
If you haven’t learned scanning yet, start with the scanning technique first!
What's Elimination
Elimination is a very simple technique. We scan a row/column/house and see what numbers are missing.
Here, we can see that the numbers 1, 6 and 8 are missing in the first row of our puzzle.
But if we look at the last cell of our row, we can scan the column to see that both 1 and 8 are in the column. Therefore, the only missing number that could go in the cell of our first row is a 6!
Here, we can see that the numbers 1, 6 and 8 are missing in the first row of our puzzle.
But if we look at the last cell of our row, we can scan the column to see that both 1 and 8 are in the column. Therefore, the only missing number that could go in the cell of our first row is a 6!
In Not Evil Sudoku, you can configure notes to help you keep track of possible numbers for each cell.
Settings: Notes
Each time you use a technique, more of the board is revealed and new opportunities arise!
Now that you’ve mastered both scanning and elimination, you have the fundamental tools to solve most easy sudoku puzzles!
You’re ready to graduate to slightly trickier puzzles. Next up, hidden singles.
Download Not Evil Sudoku for iPhone 🪄