leetcode 232. Implement Queue using Stacks

https://leetcode.com/problems/implement-queue-using-stacks/description/

Implement Queue using Stacks - LeetCode

 

class MyQueue:
 
    def __init__(self):
        self.input = []
        self.output = []
 
    def push(self, x: int) -> None:
        self.input.append(x)
        
 
    def pop(self) -> int:
        self.peek()
        return self.output.pop()
 
    def peek(self) -> int:
        if not self.output:
            while self.input:
                self.output.append(self.input.pop())
        return self.output[-1]
        
 
    def empty(self) -> bool:
        return self.input == [] and self.output == []
        
 
 
# Your MyQueue object will be instantiated and called as such:
# obj = MyQueue()
# obj.push(x)
# param_2 = obj.pop()
# param_3 = obj.peek()
# param_4 = obj.empty()