Medium Sudoku

How to play

Medium grids start with 32 givens. You will usually need notes for a few cells where more than one digit still fits.

1. Fill every row, column and 3×3 box with the digits 1 to 9, each used once.
2. Tap a cell, then tap a number. On a computer you can type digits and move with the arrow keys.
3. Switch on Notes (or press N) to pencil in candidates. Placing a digit clears it from the notes in the same row, column and box.
4. Repeated digits turn red straight away. Check marks any cell that differs from the solution; Hint fills one cell for you.

Tips for medium grids

• Use hidden singles: a digit that fits in only one cell of a row, column or box must go there.
• Keep notes up to date. Placing a digit removes it from notes in the same row, column and box.

About sudoku

Sudoku is a logic puzzle played on a 9×9 grid divided into nine 3×3 boxes. The goal is to fill every row, every column and every box with the digits 1 to 9, each exactly once. Some digits, called givens, are already placed, and the fewer givens a grid has, the harder it usually is.

The modern puzzle first appeared as “Number Place” in Dell Magazines in 1979 and is credited to the American puzzle maker Howard Garns. The Japanese publisher Nikoli popularised it in the 1980s and gave it the name Sudoku.