How to pass the post title value to the ACF field?

Here is my situation:
1.I want to pass the post title value to the ACF field after I click the "publish" button.
2.I found the relevent API of ACF here:
http://www.advancedcustomfields.com/resources/functions/update_field/
3.My field_key is field_53429cb8f4c7c.
4.However,I can't integrate the codes.So,can somebody help me to write some example codes?Thanks!