参考题225
class MyQueue:
def __init__(self):
"""
Initialize your data structure here.
"""
self.stack = []
def push(self, x: int) -> None:
"""
Push element x to the back of queue.
"""
self.stack.append(x)
def pop(self) -> int:
"""
Removes the element from in front of queue and returns that element.
"""
self.stack = self.stack[::-1]
res = self.stack.pop(-1)
self.stack = self.stack[::-1]
return res
def peek(self) -> int:
"""
Get the front element.
"""
self.stack = self.stack[::-1]
res = self.stack.pop(-1)
self.stack.append(res)
self.stack = self.stack[::-1]
return res
def empty(self) -> bool:
"""
Returns whether the queue is empty.
"""
return not bool(self.stack)
# 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()