Explanation : Case I :– if A = 0 0 0 0 0 0 0 ...
then always else part is execute so f (wanter) where counter = 0 is executed n times.
As given in clvestion complexity of f(o) is O (1) So O (1) + O (1)..... b times ⇒ O (n)
Case II : if A = [1, 1,.................1]
the loop execute n time and only if statment is executed hence complexity is O (n).
Case III : if A = [1,0,1,0,1,0..........]
or A = [0,1,0,1,0,1...................]
or any other case.
Both if and else is executed but every time when
else part is executed counter is again set to O.
Hence complexity is O (n).