Solution: Implement Queue Using Stacks
Understand how to design a queue by using two stacks to maintain FIFO order. Learn to implement Push to reorder elements, Pop and Peek operations with constant time complexity, and use Empty to check the queue status. This lesson helps you apply stack operations to simulate a queue efficiently.
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Statement
Design a custom queue, MyQueue, using only two stacks. Implement the Push(), Pop(), Peek(), and Empty() methods:
- Void Push(int x): Pushes element to the back of the queue.
- Int Pop(): Removes and returns the element from the front of the queue.
- Int Peek(): Returns the element at the front of the queue.
- Boolean Empty(): Returns TRUE if the queue is empty. Otherwise FALSE.
You are required to only use the standard stack operations, which means that only the Push() to top, Peek() and Pop() from the top, Size(), and Is Empty() operations are valid.
Note: In some interview questions, Void Push(int x) and Int Pop() might be referred to as Void Enqueue(int x) and Int Dequeue(), respectively.
Constraints:
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x -
A maximum of ...