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class MyQueue {

Stack<Integer> stack;

Stack<Integer> queue;

/** Initialize your data structure here. */

public MyQueue() {

stack = new Stack<>();

queue = new Stack<>();

}

/** Push element x to the back of queue. */

public void push(int x) {

stack.push(x);

}

/** Removes the element from in front of queue and returns that element. */

public int pop() {

if(queue.isEmpty())

{

while(!stack.isEmpty())

queue.push(stack.pop());

}

return queue.pop();

}

/** Get the front element. */

public int peek() {

if(queue.isEmpty())

{

while(!stack.isEmpty())

queue.push(stack.pop());

}

return queue.peek();

}

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

public boolean empty() {

return stack.isEmpty() && queue.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();

*/