Question

python 怎样返回一个树中正好有两个子节点的节点数量?

class RefBinaryTree:
def __init__(self,data,left=None,right=None):
self.key = data
self.left = left
self.right = right

def get_number_with_2child(self):
pass

def get_left_subtree(self):
return self.left

def get_right_subtree(self):
return self.right

def get_value(self):
return self.key

Answer 1

def get_number_with_2child(self):
    if self.left and self.right:
        return 1+self.left.get_number_with_2child()+self.right.get_number_with_2child()
    elif self.left:
        return self.left.get_number_with_2child()
    elif self.rught:
        return self.right.get_number_with_2child()
    else:
        return 0