Implement Queue using Two Stacks

Implement a queue using two stacks. In the initial implementation, the time complexity for each enqueue and dequeue operation is O(n). Then, improve your implementation to make the time complexity O(1) for enqueue and dequeue operations. Example: Input: 5 push 1 push 2 pop push 3 pop Output: 1 2 Constraints: The number of operations does not exceed 1000. All input integers are integers. Example Input 5 push 1 push 2 pop push 3 pop