Double Sudoku: Rules and Explanatory Diagrams
A double Sudoku is a variant of the classic Sudoku that introduces a second grid superimposed on the first one.
The two grids share certain cells.
1. Each grid must follow the classic Sudoku rules:
- fill each empty cell with a number between 1 and 9.
- each row, column, and block (3x3 box) must contain each number from 1 to 9 exactly once.
2. The shared cells between the two grids must simultaneously satisfy the constraints of both grids.
Rows
Columns
Blocks (3x3 boxes)
