A Shinro puzzle consists of an 8x8 board, arrows and numbers on each row and column. The objective of the game is to place 12 holes in the puzzle. But it is not that simple. The numbers on each row and column are the number of holes you must place on the respective rows and columns. Makes sense Well, there is more. To spice things up, there are arrows on the puzzle. Each arrow must be pointing to at least one hole. The puzzle will be solved once all 12 holes are placed on the right place.