Exercise: Free Coffee Cups in Swift

For each of the 6 coffee cups I buy, I get a 7th cup free. In total, I get 7 cups.

Knowing that I paid for cups cups, compute and print the total number of cups I would get (number of cups I paid for + number of cups I got for free).

Example:

For example, if cups was 12, the answer would be 14.

Why? Because I paid for 12 cups and I got 2 for free, which is a total of 14 cups.