$5.$ Consider the following algorithm that updates the values in the array A$.$

$($a$)(3$ marks$)$ Compute the time complexity of this algorithm in the best case. You must explain how you computed the time complexity, and you must give the order of the complexity.

$($b$)(3$ marks$)$ Compute the time complexity of this algorithm in the worst case. You must explain how you computed the time complexity, and you must give the order of the complexity.

Data: Array A storing n integer values Result: None i $0$; while i $<$ n do if i $=0$ then

step $1$

end else if A$[$i$]>0$ then A$[$i$]$A$[$i$]$; step $1$;

end i $$ i $+$ step; end