class MyQueue {
        private Deque<Integer> deque1;
        private Deque<Integer> deque2;


        /** Initialize your data structure here. */
        public MyQueue() {
            deque1 = new ArrayDeque<>();
            deque2 = new ArrayDeque<>();
        }

        /** Push element x to the back of queue. */
        public void push(int x) {
            deque1.push(x);
        }

        void copy(Deque<Integer> deque1, Deque<Integer> deque2) {
            while(!deque1.isEmpty()) {
                deque2.push(deque1.pop());
            }
        }

        /** Removes the element from in front of queue and returns that element. */
        public int pop() {
            copy(deque1, deque2);
            int res = deque2.pop();
            copy(deque2, deque1);
            return res;
        }

        /** Get the front element. */
        public int peek() {
            copy(deque1, deque2);
            int res = deque2.peek();
            copy(deque2, deque1);
            return res;
        }

        /** Returns whether the queue is empty. */
        public boolean empty() {
            return deque1.isEmpty();
        }
    }

/**
 * Your MyQueue object will be instantiated and called as such:
 * MyQueue obj = new MyQueue();
 * obj.push(x);
 * int param_2 = obj.pop();
 * int param_3 = obj.peek();
 * boolean param_4 = obj.empty();
 */