Traverse Matrix in Diagonal strips

Question

I thought this problem had a trivial solution, couple of for loops and some fancy counters, but apparently it is rather more complicated.

So my question is, how woul

Answer 1

Just in case somebody needs to do this in python, it is very easy using numpy:

#M is a square numpy array    
for i in range(-M.shape[0]+1, M.shape[0]):
    print M.diagonal(offset=i)