代码如下:

#include <iostream>
#include <deque>
using namespace std;template<typename T,typename Con = deque<T>>
class Stack
{
public:Stack() {}void Push(const T &x) {_c.push_back(x);}void Pop(){_c.pop_back();}T & Top(){return _c.back();}const T &Top() const{return _c.back();}size_t Size() const{return _c.size();}bool Empty() const{return _c.empty();}private:Con _c;
};int main()
{Stack<int>s;s.Push(1);s.Push(2);s.Push(3);s.Push(4);cout << s.Size() << endl;cout << s.Top() << endl;s.Pop();s.Pop();cout << s.Size() << endl;cout << s.Top() << endl;return 0;
}

测试结果: