怎么用vector作为底层结构实现queue

如题，pop函数该怎么写，这是我找到的vector实现stack的代码
template
class Stack {
public:
Stack()
{
v.reserve(capacity);
}

bool empth const() 
{
    return v.empty();
}

void push(const T& e)
{
    v.push_back(e);
}

T& pop()
{
    T e = v.back(); 
    v.pop_back();   
    return e;
}

T& top()
{
    return T.back();
}

private:
vector v;
};

https://www.cnblogs.com/peformer/p/8034956.html