As pointed out by Raphael, it depends on the machine model. Under the assumptions of the RAM model of computation ...
- Simple operations (+, -, call, return, etc.) take one time step.
- Loops and subroutines are not simple operations: they may involve many of them.
- Memory accesses (e.g., indexing into an array) take one time step.
... you counted correctly operations [1-4] and 7. As for operation 5, it depends: the subroutine call does count as one single-step operation (according to assumption 1), but the subroutine itself doesn't: it is a composite operation (according to assumption 2). Finally, I would not consider passing
A as a parameter to be an operation:
A affects running time when it is accessed within the
Sum subroutine, not in the subroutine call.