Goal and options: To save money on your water bill
output answer: Put a brick in your toilet tank. You'll save a brick's worth of water every time you flush the toilet.

Goal and options: To the move the typing cursor left or right on an iPhone,
output answer: hold down the space bar and then swipe your finger left or right.

Goal and options: To open up "my computer" on a Windows PC,
output answer:
hit the buttons "Windows" and "E".