数据结构练习（16）用两个栈实现队列

#include <stack>
#include <cassert>
using namespace std;

template <typename T> class CQueue
{
public:
CQueue() {}
~CQueue() {}

void append_tail(const T& element);
void delete_head();

private:
stack<T> m_stack1;
stack<T> m_stack2;
};

template <typename T> void CQueue<T>::append_tail(const T& element)
{
m_stack1.push(element);
}

template <typename T> void CQueue<T>::delete_head()
{
if (m_stack2.size() <= 0)
{
while (m_stack1.size())
{
m_stack2.push(m_stack1.top());
m_stack1.pop();
}
}
assert(m_stack2.size() > 0);
m_stack2.pop();
}

int main()
{
CQueue<int> q;
q.append_tail(10);
q.delete_head();
return 0;
}