"""Leetcode 225. Implement Stack using Queues
Easy

URL: https://leetcode.com/problems/implement-stack-using-queues/

Implement the following operations of a stack using queues.
- push(x) -- Push element x onto stack.
- pop() -- Removes the element on top of the stack.
- top() -- Get the top element.
- empty() -- Return whether the stack is empty.

Example:
MyStack stack = new MyStack();
stack.push(1);
stack.push(2);  
stack.top();   // returns 2
stack.pop();   // returns 2
stack.empty(); // returns false

Notes:
- You must use only standard operations of a queue -- which means only 
  push to back, peek/pop from front, size, and is empty operations are valid.
- Depending on your language, queue may not be supported natively. You may simulate
  a queue by using a list or deque (double-ended queue), as long as you use only
  standard operations of a queue.
- You may assume that all operations are valid (for example, no pop or top
  operations will be called on an empty stack).
"""

class MyStack(object):
    def __init__(self):
        """
        Initialize your data structure here.
        """
        pass

    def push(self, x):
        """
        Push element x onto stack.
        :type x: int
        :rtype: None
        """
        pass

    def pop(self):
        """
        Removes the element on top of the stack and returns that element.
        :rtype: int
        """
        pass

    def top(self):
        """
        Get the top element.
        :rtype: int
        """
        pass

    def empty(self):
        """
        Returns whether the stack is empty.
        :rtype: bool
        """
        pass


def main():
    # obj = MyStack()
    # obj.push(x)
    # param_2 = obj.pop()
    # param_3 = obj.top()
    # param_4 = obj.empty()
    pass


if __name__ == '__main__':
    main()

Add lc0225_implement_stack_using_queues.py