) Complete the code for the class SpecialQueue below, which implements a queue in terms of two stacks. Assume that the stacks are implemented by the class IntStack with the interface from Problem 2. class SpecialQueue { public: void enqueue(const int& x) { // TODO: you code here } void dequeue(int& x) { // TODO: you code here } private: IntStack inbox; IntStack outbox; };

(Problem 2 Interface)

class IntList {

private:

struct Node {

int data;

Node* next;

};

Node* head;

unsigned int size;

public:

class iterator {

int& operator*() const;

iterator& operator++();

};

class const_iterator {

const int& operator*() const;

const_iterator& operator++();

};

// returns an iterator associated with the first element in the list

iterator begin();

// returns an iterator associated with the last element in the list

iterator end();

// returns the last element in the list

int pop_back();

// returns the first element in the list

int pop_front(); // adds x to the end of the list void push_back(const int& x); // adds x to the beginning of the list void push_front(const int& x);

// returns the number of elements in the list

unsigned int size();

};