reversing the order of an array in ruby

Question

a = [12,16,5,9,11,5,4]
# => [12, 16, 5, 9, 11, 5, 4]
a.reverse
# => [4, 5, 11, 9, 5, 16, 12]

I’m not seeing what you’re seeing.

Edit: Expanding on what Ben noticed, you may be reversing a string.

"12,16,5,9,11,5,4".reverse
# => "4,5,11,9,5,61,21"

If you have to reverse a string in that manner, you should do something like the following:

"12,16,5,9,11,5,4".split(",").reverse.join(",")
# => "4,5,11,9,5,16,12"