Calcudoku(killer sudoku) description

Calcudoku is a popular variant of killer sudoku.

The key difference between calcudoku and killer sudoku is that it is allowable to repeat a number within a cage in the way that it is never allowable in killer sudoku.

Generally the box regions are dropped so in calcudoku the major regions are just the rows and columns. Also the dotted cages of killer sudoku are replaced with thick bordered regions as you might see in jigsaw sudoku.

Some calcudoku puzzles follow the rules of killer sudoku in that all the arithmetical regions are sum regions, but this is by no means always the case. The rules of calcudoku allow for the arithmetic required to be addition, subtraction, division or multiplication.