Bricks Falling When Hit

You are given an m x n binary grid, where each 1 represents a brick and 0 represents an empty space. A brick is stable if:

• It is directly connected to the top of the grid, or
• At least one other brick in its four adjacent cells is stable.

You are also given an array hits, which is a sequence of erasures we want to apply. Each time we want to erase the brick at the location hits[i] = (row_i, col_i). The brick on that location (if it exists) will disappear. Some other bricks may no longer be stable because of that erasure and will fall. Once a brick falls, it is immediately erased from the grid (i.e., it does not land on other stable bricks).

Return an array result, where each result[i] is the number of bricks that will fall after the i^th erasure is applied.

Note that an erasure may refer to a location with no brick, and if it does, no bricks drop.