Much like this OP asked in Java, I'd like to know how to do in Ruby:

[How to compare a date - String in the custom format “dd.MM.yyyy, HH:mm:ss” with another one?](https://stackoverflow.com/questions/17643743/how-to-compare-a-date-string-in-the-custom-format-dd-mm-yyyy-hhmmss-with)

I have these two strings, which convey dates and time and I would like to find the older one of the two:

20141024\_133641
20141024\_142440

The format is %Y%m%d\_%H%M%S ; which makes the former the older one in this case.