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Help – Sudoku Basics 


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Read the Sudoku help page for the rules, and the techniques potentially required to solve BrainBashers Sudoku.

Sudoku is a game of logic – the object is to complete the grid such that every row, every column, and every 3 × 3 block contains the digits from 1 to 9. There is no mathematics required to solve the puzzles, just pure logic and reasoning.


The Basics 1
The rows and columns are labelled 1 to 9, as are the 3 × 3 blocks.

Each cell is uniquely referenced, e.g. R2C5, for example, means the single cell in Row 2 and Column 5. Also, e.g. Block7 is the block numbered 7.

The Basics 2
This is a completed Sudoku.

The Basics 3
Each row, column and 3 × 3 block contains the digits 1 to 9.

The 'buddies' of a square are the squares that share a row, column or 3 × 3 block. e.g. the buddies of R3C7 are shown below.

Every square has 20 buddies.

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