What to do if your facebook account got spammed?

This is example of spam victim:
When you click the URL,Facebook will ask you for permission

It will share the link automatically without user noticing it.

How to dealt with this thing?
Follow this step:

1.Open facebook.com,then go to setting
2.In the left,select Apps(https://www.facebook.com/settings/?tab=applications)
3.Now search for any suspicious apps.
4.Remove any permission for apps that suspicious you.
5.Done.Congratulation.Now you are free.