2768. Number of Black Blocks

You are given two integers m and n representing the dimensions of a 0-indexed m x n grid. You are also given a 0-indexed 2D integer matrix coordinates, where coordinates[i] = [x, y] indicates that the cell with coordinates [x, y] is colored black. All cells in the grid that do not appear in coordinates are white. A block is defined as a 2 x 2 submatrix of the grid. More formally, a block with ce