Number of Operations in an Algorithm

Question

Hi,

I am taking a CS class and one exercise asks me to count the number of operations in a given algorithm containing a for loop. Can you explain the number of operations for size = n in the following algorithm please?

int funcExercise7(int list[], int size) {
int sum = 0
for (int index = 0; index < size, index++)
sum = sum + index;
return sum;
}

It seems to me it should be 5n + 3. 1 for "sum =...", 1 for "return...", 1 to check conditions when the loop closes, and 5n per loop.

However, the book says it is 4n + 3. I assume I should not be counting one of the operations in the for loop? Can you break this down a bit more for me?

Thanks.

Answer 1

Checking index < size per loop, index++ per loop, sum + index per loop, and sum = sum + index per loop should be four. Then sum = 0, index = 0, and return sum should be three. 4n + 3

Answer 2

Yeah that makes sense. Thank you.