Finding degrees from one number to the next (locker combination)

The lock has a dial with 40 calibration marks numbered 0 to

39.

given the initial position of the dial of the lock and first calbaration I have to find the degrees turned

I have to:

turn dial clockwise 2 full turns and stop at the first number of the combination

Ok that is fine from this I know that one complete turn is 360 since there are 40 calibrations 360/40=9. Therefore there is 9 degrees between each number. I have to make two complete turns which means I add 720 degrees plus how far the calibration is.

This is what I have so far:

short num;

cout << "please enter start position";

cin >> num

short numx;

cout << "please enter first calibraion";

cin >> numx

ya I'm kind of lost after that since the degrees change depending on what the numbers are. Ya I could use some help thanks.