Original puzzle of Nikolihttps://live.gnome.org/Hitori
Hitori is played with a grid of squares or cells, and each cell contains a number.
The objective is to eliminate numbers by filling in the squares such that remaining cells do not
contain numbers that appear more than once in either a given row or column.
Filled-in cells cannot be horizontally or vertically adjacent, although they can be diagonally
adjacent. The remaining un-filled cells must form a single component connected horizontally