225. Implement stack with queue

Please use only two queues to implement one LIFO （LIFO） The stack , And supports all four operations of ordinary stack （push、top、pop and empty）.

Realization MyStack class ：

void push(int x) Put the element x Press into the top of the stack .
int pop() Remove and return the top element of the stack .
int top() Back to top of stack element .
boolean empty() If the stack is empty , return true ; otherwise , return false .

Review the Java Of Stack and queue .
Stack： One class , Inherit Vector , Thread safety , Poor performance , It is not recommended to use .
push()
pop()
peek()
Queue： An interface , Inherit Collection,LinkedList Inherited the interface .
add offer
remove poll
Element peek

Ideas ：
Two queues , A simulation stack , An auxiliary .
push When the elements , Adjust to the order of stacks .
follow-up Get stack top element , Delete stack top element , Don't move .