The input comes in the form is a string of coordinates that paints the walls of the board.
We'll build a clerk RGB image visualizater for our state.
Now we have to code up the core logic of the puzzle. We start dropping sand, where the physics of sand is that it falls straight down if able, otherwise it tries to go down and left and finally it tries to go down and right.
Now there is a big floor at the bottom that sand can land on and we have to keep filling up with sand until we block the source.