C++ implementation of queue and stack

fifolifo.cpp

#include <list>
#include <iostream>

using namespace std;

// Implement Q class
class Q{
public:
  Q();
  ~Q();
  void enqueue(int n);
  int dequeue();
private:
  list<int> queue;
};

Q::Q(){
  list<int> queue;
}
Q::~Q(){}
void Q::enqueue(int n){
  queue.push_back(n);
}
int Q::dequeue(){
  int n = queue.front();
  queue.pop_front();
  return n;
}

//Implement Stack class
class Stack{
public:
  Stack();
  ~Stack();
  void push(int n);
  int pop();
private:
  list<int> stack;
};
Stack::Stack(){
  list<int> stack;
}
Stack::~Stack(){}
void Stack::push(int n){
  stack.push_back(n);
}
int Stack::pop(){
  int n = stack.back();
  stack.pop_back();
  return n;
}
// Create examples
int main(){
  Q q;
  Stack s;
  for(int i=0;i<5; i++){
    q.enqueue(i);
    s.push(i);
  }
  cout<<"Empty the queue:"<<'\n';
  //empty the queue: 0,1,2,3,4
  for(int i=0;i<5;i++){
    cout<<q.dequeue()<<'\n';
  }
  cout<<"Empty the stack:"<<'\n';
  // empty the stack: 4,3,2,1,0
  for(int i=0;i<5;i++){
    cout<<s.pop()<<'\n';
  }
}