There are two things you should take notice of. The color of the tint and what button is missing in each of the tints. The color of the tint will give you the position information and the missing button will give you the button information.
Set the tint to the first letter in the code. The bottom letter will give you the correct button.
Once again, it’s not what buttons are shown, but which ones aren’t…
Add two numbers and subtract from the sum of two other numbers.
That concludes the hints for Hack This Game 3, Good Luck!