Compilers usually execute recursive procedures by using a stack that contains pertinent infor$-$

mation, including the parameters values, for each recursive call. The information for the most

recent call is at the top of the stack, and the information for the initial call is at the bottom.

When a procedure is invoked, its information is pushed onto the stack; when it terminates,

its information is popped. Since we assume that array parameters are represented by pointers,

the information for each procedure call on the stack requires O$(1)$ stack space. The stack

depth is the maximum amount of stack space used at any time during a computation.

$($b$)$ Describe a scenario in which the stack depth of Quicksort$$ is $\backslash$Theta $($n$)$ on an n$-$element input

array.