Corral #64
A single closed loop must be drawn in the grid along the grid lines, which does not pass through any grid point more than once but does not necessarily pass through all grid points. All number cells must be located inside the loop.
A number indicates how many cells you can see in total within the loop when you look from the number cell to the north, south, east, and west. The cell with the number counts once.
Other numbers do not obstruct the view, but you cannot look through cells outside the loop into other parts of the loop.