About this puzzle
Mathdoku - also known as "CalcuDoku" or "Square Wisdom" - is a logical math puzzle. The objective of Mathdoku is to fill the grid with the numbers 1 to 9 (or whatever the grid dimension is) such that each row and each column contains only one instance of each number.
In addition, each outlined group of cells contains digits which achieve a specified result using the specified mathematical operation (+, -, ×, ÷). Unlike Killer Sudoku, numbers can repeat within a group of cells.