Problem 579. Spiral In

Create an m by n matrix filled with sequential integers starting from 1 and arranged in a counterclockwise spiral that hugs the outside border and begins in the upper left corner.

For example:

>> spiralIn(4,5)
ans =
   1    14    13    12    11
   2    15    20    19    10
   3    16    17    18     9
   4     5     6     7     8