Find the cumulative minimum of an array without using the built-in function cummin (and a few others). Your function should act identically to cummin, allowing the same inputs.

Examples

If X = [0 4 3
        6 5 2]

cumin(X,1) is [0 4 3  and cumin(X,2) is [0 0 0
               0 4 2]                    6 5 2]

cumin(X,1,'reverse') is [0 4 2  and cumin(X,2,'reverse') is [0 3 3
                         6 5 2]                              2 2 2]

Also,
cumin([8 9 1 10 6 1 3 6 10 10]) returns [8 8 1 1 1 1 1 1 1 1]

cumin([8 9 1 10 6 1 3 6 10 10]') returns [8 8 1 1 1 1 1 1 1 1]'

See also cumax.