STL-queue模拟实现

#include<list>
#include<assert.h>
#include<deque>
#include<iostream>
using std::cout;
using std::endl;
using std::cin;
namespace test
{
    //template<class T, class Containers = std::list<T>>
    template<class T, class Containers = std::deque<T>
>
    class queue
    {
    private:
        Containers _con;
    public:
        void push(const T& x)
        {
            _con.push_back(x);//尾插
        }
        void pop()
        {
            _con.pop_front();//头删
        }
        const T& front()
        {
            return _con.front();
        }
        const T& back()
        {
            return _con.back();
        }
        bool empty()
        {
            return _con.empty();
        }
        size_t size()
        {
            return _con.size();
        }

    };

    void test_quque1()
    {
        queue<int> q;
        q.push(1);
        q.push(2);
        q.push(3);
        while (!q.empty())
        {
            std::cout << q.front() <<" ";
            q.pop();
        }
    }

}