问题描述
我正在做关于 Python 基础知识的 leetcode 问题。我在 leetcode 上收到如下错误代码。
TypeError: reverseString() takes 1 positional argument but 2 were given ret = Solution().reverseString(param_1) Line 28 in _driver (Solution.py) _driver()
class Solution:
def reverseString(s: List[str]) -> None:
if len(s)==0:
return s
else:
return Solution.reverseString(s[1:])+s[0]
解决方法
from sqlalchemy.ext.hybrid import hybrid_property
class Parent(Base):
...
children = relationship("Child",order_by="Child.age")
@hybrid_property
def youngest_child(self):
"""
children are already sorted by their age in the relationship.
This offers an advantage in performance when children are frequently
accessed through their sorted property.
"""
return self.children[0] if self.children
# - - - - - - - - - - - - - - - - - -
# Another approach – without pre-defined ordering
class Parent(Base):
...
# Don't order the children
children_no_order = relationship("Child")
@hybrid_property
def youngest_child_no_order(self):
"""
children are not automatically sorted by their age.
Do so with a subquery hybrid.
"""
query = Child.query\
.filter(Child.parent_id == self.id)
.order_by(Child.age)\
.first()
# I chose to write this query in this format bc it helps with debugging
# You could just as easily return the query without saving its state...
return query
是一个类方法，但您没有将 reverseString 参数定义为第一个参数。您应该将其作为第一个参数，或者使用 @staticmethod decorator。这在现有的帖子中有更好的解释：TypeError: method() takes 1 positional argument but 2 were given
您需要提供一个参数而不是两个。