代码如下:

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

测试结果: