class CQueue:
def __init__(self):
self.inner = []
self.outer = []
def appendTail(self, value: int) -> None:
self.inner.append(value)
def deleteHead(self) -> int:
if len(self.inner) ==0 and len(self.outer)== 0: # 啥都沒就別瞅了
return -1
if len(self.outer) != 0:
return self.outer.pop()
while len(self.inner) != 0:
self.outer.append(self.inner.pop())
return self.outer.pop()
https://leetcode-cn.com/problems/yong-liang-ge-zhan-shi-xian-dui-lie-lcof/