Examine the following declarations and definitions for array$-$based implementations for Stack and Queue ADTs. Assume that exception class PushOnFullStack and class

PopOnEmptyStack have been defined and are available. Read the following code segment and fill in blank #$3.$

class StackType

$\{$

public:

StackType$()$;

void Push$($StackltemType item$)$;

void Pop$()$;

private:

int top;

ItemType items$[$MAX$\_$STACK$]$;

$\}$;

void StackType::StackType$()$

$\{$

top $=-1$;

$\}$

void StackType::Push$($ItemType item$)$

$\text{'}1$

$\frac{\frac{?}{?}}{2}$

$3$

$//4$

J

class QueType

$\{$

public:

$//$ prototypes of QueType operations go here private:

int front;

int rear;

ItemType items$[$MAX$\_$QUEUE$]$;

$\}$

void QueType::QueType$()$

$\{$

front $=$ MAX$\_$QUEUE $-1$;

rear $=$ MAX$\_$QUEUE $-1$;

$\}$

Boolean QueType::IsEmpty$()$

$\{$

return $($rear $==$ front$)$;

$\}$

void QueType::Enqueue$($ItemType item$)$ &

;( $\frac{?}{?}$

;( $\frac{?}{?}$