def constructtree(self, preorder, inorder, k1, Lk1, k2, Lk2):
rootval = preorder[k1]
root = BinaryTreeNode(rootval)
if k1 == Lk1:
if k2 == Lk2 and preorder[k1] == inorder[k2]:
return root
else:
raise ValueError
rootino = k2
while rootino <= Lk2 and inorder[rootino] != rootval:
rootino += 1
if rootino == Lk2 and inorder[rootino] != rootval:
raise ValueError
leftlength = rootino - k2
leftpreo = k1 + leftlength
if leftlength > 0:
root.left_ = self.constructtree(preorder, inorder, k1 + 1,
leftpreo, k2, rootino - 1)
if leftlength < (Lk1 - k1):
root.right_ = self.constructtree(preorder, inorder, leftpreo + 1,
Lk1, rootino + 1, Lk2)
return root
def deserializetree(self, ls):
if len(ls) <= 0:
return None
val = ls.pop(0)
root = None
if val != '$':
root = BinaryTreeNode(int(val))
root.left_ = self.deserializetree(ls)
root.right_ = self.deserializetree(ls)
return root
