Problem 59. Pattern matching

Given a matrix, m-by-n, find all the rows that have the same "increase, decrease, or stay same" pattern going across the columns as the first row does. Do not list the row as a match to itself.

Example:

 Input  a = [1 2 3 0
             5 6 7 9
             2 7 8 7]
 Output b is 3

since the third column follows the increase-increase-decrease pattern used in vector a.