Implement Queue using Stacks LeetCode solution in Java

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class MyQueue {
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  private final Deque<Integer> stack = new ArrayDeque<>();
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  private final Deque<Integer> temp = new ArrayDeque<>();
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  /** Initialize your data structure here. */
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  public MyQueue() {}
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  /** Pushes element x to the back of the queue. */
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  public void push(int x) {
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    stack.push(x);
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  }
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  /**
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   * @return the element at the front of the queue and remove it.
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   */
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  public int pop() {
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    while (stack.size() > 1) temp.push(stack.pop());
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    var val = stack.pop();
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    while (!temp.isEmpty()) stack.push(temp.pop());
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    return val;
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  }
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  /**
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   * @return the element at the front of the queue.
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   */
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  public int peek() {
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    while (stack.size() > 1) temp.push(stack.pop());
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    var val = stack.peek();
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    while (!temp.isEmpty()) stack.push(temp.pop());
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    return val;
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  }
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  /**
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   * @return true if the queue is empty, false otherwise.
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   */
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  public boolean empty() {
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    return stack.isEmpty();
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  }
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}