How many elementary operations are used in the following algorithm?

Question

Step 1 Set S = a, k = 0 , and t = a
Step 2 while k < n
(a) Replace t with t+d
(b) Replace S with S+t
(c) Replace k with k+1

endwhile
Step 2 Print S

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My answer was: 4*n+1
I don't know if it is right :(

Answer 1

if k=>n, there is only one operation, the test.

If k<n, then each time the test occurs, there are four operations(test, replace, replace, replace), and one final operation the test.

4n+1 is correct.

Answer 2

Step 1 Set a=1, b=1, c=2,and k=0
Step 2 while k < n
(a) Replace c with a+b
(b) Replace a with b
(c) Replace k with k+1
endwhile

Step 3 Print b