Sum the elements of a square matrix that lie on either the major diagonal or anti-diagonal. (Include all elements that are part of either of the diagonals).
the description of your problem is wrong, not the same as test suits. the either..or... should be both...and...
I updated the description to clarify the ambiguity mentioned by Gareth Lee on 1 May 2015.
With apologies for the 2 year delay, I've updated the description to be a little more explicit.
I hadn't seen this approach to masking the complexity of a solution before. Obvious in hindsight of course.
Extract leading non-zero digit
888 Solvers
270 Solvers
255 Solvers
Reverse the elements of an array
464 Solvers
Calculate the derivative of a polynomial
132 Solvers