class MyStack {

private Queue<Integer> p = new ArrayDeque<>();

private Queue<Integer> q = new ArrayDeque<>();

/** Initialize your data structure here. */

public MyStack() {

}

/** Push element x onto stack. */

public void push(int x) {

p.offer(x);

while(!q.isEmpty()) p.offer(q.poll());

swap();

}

private void swap() {

Queue<Integer> k = p;

p = q;

q = k;

}

/** Removes the element on top of the stack and returns that element. */

public int pop() {

return q.poll();

}

/** Get the top element. */

public int top() {

return q.peek();

}

/** Returns whether the stack is empty. */

public boolean empty() {

return q.isEmpty();

}

}

/**

* Your MyStack object will be instantiated and called as such:

* MyStack obj = new MyStack();

* obj.push(x);

* int param_2 = obj.pop();

* int param_3 = obj.top();

* boolean param_4 = obj.empty();

*/