I'm trying to use inheritance to create a simple binary tree, but it's
not going so well... here's what I pull from the documentation for
super()
"super( type[, object-or-type])
Return the superclass of type. If the second argument is omitted the
super object returned is unbound. If the second argument is an object,
isinstance(obj, type) must be true. If the second argument is a type,
issubclass(type2, type) must be true. super() only works for new-style
classes.
A typical use for calling a cooperative superclass method is:
class C(B):
def meth(self, arg):
super(C, self).meth(arg)
"
So here's what I do:
class Node:
def __init__(self, val=0, prnt = None):
self.value = val
self.parent = prnt
class Tree(Node):
def __init__(self, val=0):
self.root = super(Tree, self).__init__(val)
self.leftChild = None
self.rightChild = None
def addChild(self, value):
if self.root == None:
self.__init__(value)
else:
n = self.root
while(n is not None):
if(n.leftChild == None and n.rightChild == None):
n.leftChild = Node(value, n)
elif(n.rightChild == None):
n.rightChild = Node(value, n)
else:
if(n.leftChild.leftChild is not None and
n.leftChild.rightChild is not None):
n = n.rightChild
else:
n = n.leftChild
def printTree(self):
if self.root == None:
print "None"
else:
n = self.root
print n.value
while(n is not None):
if(n.leftChild is None):
print str(n.value) + "'s left child is None"
elif(n.rightChild is None):
print str(n.value) + "'s right child is None"
else:
if(n.leftChild.leftChild is not None and
n.leftChild.rightChild is not None):
n = n.rightChild
else:
n = n.leftChild
def main():
play = Tree(1)
play.addChild(2)
play.addChild(3)
play.addChild(4)
play.addChild(5)
play.printTree()
if __name__ == "__main__":
main()
...and here's what I get:
Traceback (most recent call last):
File "C:/Users/The_N_Channel/Desktop/funWithTrees.py", line 53, in
<module>
main()
File "C:/Users/The_N_Channel/Desktop/funWithTrees.py", line 45, in
main
play = Tree(1)
File "C:/Users/The_N_Channel/Desktop/funWithTrees.py", line 8, in
__init__
self.root = super(Tree, self).__init__(val)
TypeError: super() argument 1 must be type, not classobj
Looks to me like the super(Tree, self)__init__(val) follows the
example in the documentation, but I may be a witch. Anyone know why
this doesn't work?
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