This is your first JumpMan project that uses a variable: a word to hold a number. Click this in Topics Covered section and read up on it- you'll use variables often!
You can manipulate variables however you'd like. For example, change int counter = 0; to int counter = 1; and change counter = counter + 1 to counter = counter * 2; . Now you'll see how you can apply any math operation to a variable.
This exercise also highlights the importance of naming a variable descriptively. The 'counter' is no longer much of a counter, it's more like a 'doubler'. doubler may be a better name for the variable if you were to keep using it to double its value.