Ribbon around the frame

Problem

You're trimming a rectangular picture wide by tall centimeters with ribbon. The ribbon goes all the way around the edge and, on top of that, 10 centimeters go into the bow.

Write a function that returns how many centimeters of ribbon to buy.

A picture 10 by 5 needs 40. The 10 for the bow is added once, not once per side, and the measurements can come with decimals.

Examples

• 10, 5 → 40

• A square picture

  7, 7 → 38

• Measurements with decimals

  12.5, 4 → 43

Besides these, the challenge has hidden tests that are revealed when you submit your solution.

You start with this

def ribbon(wide, tall):
    pass

function ribbon(wide, tall) {
}