Draw a path that goes from the opening at the top of the grid to the opening at the bottom. As the path winds from one cell to the next, it can move up, down, left or right but not diagonally. It cannot pass through any cell more than once. The numbers next to the grid tell how many cells the path must pass through in the corresponding row. If a row has no number, then the path may pass through as many or as few cells as you like.