A knight is initially located in the grid above, on the square marked 1. It then proceeds to make a series of moves, never re-visiting a square, and always changing region on each move. Each row and column is visited the same number of times, as is each region.

Fill in the missing steps from the knight’s journey. The answer to this puzzle is the product of the areas of the orthogonally connected groups of empty squares in the completed grid. (Squares are “connected” if they border one another horizontally or vertically.)