How to press back button in android programatically?

I my app i have a logout functionality. If user clicks logout it goes to home screen.Now i am exiting my app by pressing back button. But what i want is i need to exit automatically(i.e Programatically) as same like as back button functionality. I know by calling finish() will do the functionality. But the thing is it goes to the previous activity.

Thanks for your help guys

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