Suppose, you are being told to write a matrix, a as input in MATLAB with having the possibility of containing zero and non-zero elements within a definite number of rows and columns. Furthermore, if you are told to count only the total non-zero elements along the diagonals (Blue and Green mark on the attached image) that are immediately next to the main diagonal (Red mark on the attached image) as output b. How will you do that?

Example: a=[1 3;4 2] and b=2;

https://drive.google.com/file/d/1vjx3D2cLbuq-gH2TC7XNYWMs3WSSObcb/view?usp=sharing