OOPs in CP?

I am asking this question as beginner to CP.
How often do you/we(competitive programmer) use OOPs concepts in competitive programming?

Not Much. Basically if you see the patterns over codechef or codeforces , it is all about implementing ds and algo concept as per the questions and test inputs. All the output will be compared with the test case output file. There is no-way to rate your code based on the OOP concept or structuring.