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Computer Science Introduction to Data Structures Building a Linked List Adding Nodes to a Linked List

Problem with .size() method

@2:05 of the video, when using the .size() method I get the following error.

TypeError: LinkedList.size() missing 1 required positional argument: 'self'

So I put the variable name in l.size(l) and it works, but that doesn't seem right. Is no one else having this issue? Tried both in VS code editor and in the workspace version.

1 Answer

Steven Parker
Steven Parker
229,788 Points

"LinkedList" is the name of the class, but size is an instance method. So you need to call it on an instance of the class instead of the class itself:

MyList = LinkedList()    # create an instance of the class
MyList.size()            # now you can call "size" on it