There are four buttons in a row on a touch screen. Two of them show circles and two show triangles.
When a button is pressed, its shape and the shapes of any buttons directly next to it change. A circle becomes a triangle and a triangle becomes a circle.
What is the smallest number of button presses needed for the screen to show four circles?
Select one option, then click Submit.
2
3
4
5
6
Select an option, then submit.
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