Normal sudoku rules apply. In addition, there is an orthogonally-connected path starting at Frogger (R9C5) that collects all flies in the grid and ends at one of the colored frogs (small circles) in the first row. The path cannot touch itself orthogonally, but can touch itself diagonally. The path also cannot go through the bushes (green cells) in the first row. Cars and logs are found in the road and the river, respectively; they appear in those regions wherever two horizontally adjacent digits sum to 10. Frogger cannot go through cars, and can only hop across logs in the river.