Goal
Fill the 9x9 grid with numbers from 1 to 9 so that each row, column, and 3x3 box contains every digit exactly once.
Rules
1. Each number from 1 to 9 must appear exactly once in each of the 9 rows.
2. Each number from 1 to 9 must appear exactly once in each of the 9 columns.
3. Each number from 1 to 9 must appear exactly once in each of the 9 sub-grids (3x3 blocks).
Tips for Beginners
* Look for rows or columns that are already mostly filled with numbers first.
* Use the Notes (pencil marks) feature to write candidates inside cells if you are not sure. This allows you to track potential options before confirming.