Location：
Please draw an arrow in the cell
The arrows point in different directions, up north, down south, left west, right east
There are spaces in the cell
The edge number represents the number of arrows corresponding to the row or column
Blocks：
Place triangles in blank cells so that all remaining blank areas are squares
A square can be upright or tilted
The number in the cell represents the number of triangles that can be stored around that number