Hidoku Game

Hidoku is a Japanese logic puzzle game in which you have to find a path on a diagram that goes through all the squares exactly once in the correct order. In general, Hidoku is very similar to sudoku, and is sometimes called a number snake. The diagram is filled with numbers from 1 to the number of cells in the diagram, each number is used exactly once, and consecutive numbers must be orthogonal or diagonally adjacent. Hidoku starts with a partially filled grid of numbers. The grid can be of any size and shape.