Sudoku Strategies: Naked Singles
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Understanding the Naked Single Sudoku Strategy
The "Naked Single" is a fundamental Sudoku solving technique, also known as a "Sole Candidate" or "Forced Digit". This strategy helps identify cells where only one number is mathematically possible.
What is a Naked Single?
A Naked Single occurs when, after examining all related cells in its row, column, and 3x3 block, only one possible digit (from 1 to 9) can fit into a specific empty cell without breaking the fundamental Sudoku rules. This is a direct consequence of other numbers already placed in the grid, which eliminate all other candidates for that cell.
How to Find a Naked Single
The easiest way to find a Naked Single is by systematically checking each empty cell. You can use "pencil marks" (writing all possible candidates in a cell) to make this process easier, or perform a visual scan for simpler puzzles.
In the illustration above, you will notice that cell "E7" is situated in 3 houses (which is true of all cells) and within those three houses every other possible digit has been used except for the number 5- making 5 the solution for the highlighted cell.
