If you are a Futoshiki player, then you know that it can be quite a challenging type of puzzle if not harder than Sudoku and different from Kakuro. The objective is to place numbers in the white squares (called cells) so that each row and column contain each of the digits only once. No duplicate digits are allowed in any row or column. Also, you will only use digits based on the size of the grid. So for example, if you are playing a 5 x 5 grid, only digits 1 through 5 will be used.
For a 8 x 8 grid, only 1 through 8 is used.
There are a few key rules in playing:
In a N x N puzzle the range of #'s must be between 1 and N.
No digit is repeated within row or column. No duplicates.
Inequality constraints must be honored: 5 > 4, 5 > 3, or 1 < 4