0232 Implement Queue using Stacks

Solved at: 221128

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Question

Implement a first in, first out (FIFO) queue using only two stacks. The implemented queue should support a regular queue's functions (push, peek, pop, and empty).

• Implement the MyQueue class:
  • void push(int x) Pushes element x to the back of the queue.
  • int pop() Removes the element from the front of the queue and returns it.
  • int peek() Returns the element at the front of the queue.
  • boolean empty() Returns true if the queue is empty, false otherwise.
• You must use only standard operations of a stack, which means only push to top, peek/pop from top, , and operations are valid.