!YesYouKen is a style of arithmetic and logical puzzle sharing several characteristics with sudoku:

• For a (n x n) puzzle fill in the numbers 1 to n.
• Each row and each column must contain each number exactly once.
• The numbers in each red outlined set of squares, called cages, must combine (in any order) to produce the target number in the top corner of the cage using the mathematical operation indicated (addition, subtraction, multiplication, or division).
• A number can be repeated within a cage as long as it is not in the same row or column.

Features:

• 5 grid sizes from 4x4 (easy) to 8x8 (challenging).
• All puzzles are randomly generated.
• Arithmetic involves addition only, addition and multiplication, or all 4 basic operations.
• Replace operation symbols by "?" leaving them as yet another unknown to be determined.
• Save/Restore helps you to try out alternative ways.
• Undo/Redo - virtually unlimited.
• Mark wrong or uncompleted rows, columns and cages.
• Enter digits by number keys or selection key only (multi-click).
• Portrait & landscape display.
• Best times table.
• Languages: English (preset), German.

Advanced feature:
Cages are composed of 1 to 5 cells. Once you get familiar with !YesYouKen you can control the game generator to create totally new cage size combinations. By default, a 4x4 puzzle (16 cells) is randomly divided into 3 two-cell cages, 2 three-cell cages and 1 four-cell cage (3-2-1). Change the preset to (4-0-2) or (8-0-0), for example. Some combinations produce interesting new puzzles, others lead to hardly solvable games - try it out and enjoy!

The trial version generates 4x4 grids only.