How to block or remove url like /show?=12334 or /login?to=239%2F type page link from google indexing?

Question

I am sharing a screenshot.

As you can see in the above screenshot. The same page indexed two times in google search result.

first with - 

example.com/postitle?show=244 

and second 

example.com/post-title

How to remove or block Show?=244 and /qa/login?to=239%2 urls from indexing . It will create any problem or not. The same page indexed two times with the show? and login? 

Please suggest the best.