return self.isUnivalTree(root.left) and self.isUnivalTree(
root.right)
def isUnivalTree1(self, root):
"""
栈
:type root: TreeNode
:rtype: bool
"""
if not root:
return None
a_stack = [root]
a_list = []
while a_stack:
node = a_stack.pop()
if node.val not in a_list:
a_list.append(node.val)
if node.left:
a_stack.append(node.left)
if node.right:
a_stack.append(node.right)
return len(a_list) == 1
if __name__ == "__main__":
# nodes = [1, 1, 1, 1, 1, None, 1]
nodes = [9, 9, 9, 9, 9, 9, 6]
root = create_tree(nodes)
flag = Solution().isUnivalTree(root)
print flag
:type root1: TreeNode
:type root2: TreeNode
:rtype: bool
"""
a1 = self.get_child_arr(root1)
a2 = self.get_child_arr(root2)
return a1 == a2
def get_child_arr(self, root):
if not root:
return []
a_stack = [root]
res = []
while a_stack:
p = a_stack.pop()
if p.left:
a_stack.append(p.left)
if p.right:
a_stack.append(p.right)
if not (p.right or p.left):
res.append(p.val)
return res
if __name__ == "__main__":
arr1 = [1, 2, 3, None, 5]
tree1 = create_tree(arr1)
# arr = Solution().leafSimilar(tree1)
arr = Solution().get_child_arr(tree1)
print arr
return t2
if not t2:
return t1
t1.val += t2.val
t1.left = self.mergeTrees(t1.left, t2.left)
t1.right = self.mergeTrees(t1.right, t2.right)
return t1
def mergeTrees1(self, t1, t2):
"""
不改变原树
:type t1: TreeNode
:type t2: TreeNode
:rtype: TreeNode
"""
if not t1 and not t2:
return None
root = TreeNode((0 if not t1.val else t1.val) +
(0 if not t2.val else t2.val))
root.left = self.mergeTrees(t1.left, t2.left)
root.right = self.mergeTrees(t1.right, t2.right)
return root
if __name__ == "__main__":
arr1 = [1, 3, 2, 5]
arr2 = [2, 1, 3, None, 4, None, 7]
tree1 = create_tree(arr1)
tree2 = create_tree(arr2)
tree = Solution().mergeTrees1(tree1, tree2)
def zigzagLevelOrder(self, root):
"""
:type root: TreeNode
:rtype: List[List[int]]
"""
res = []
def inner(node, level):
if not node:
return []
if len(res) <= level:
res.append([])
if level % 2 == 0:
res[level].append(node.val)
else:
res[level].insert(0, node.val)
if node.left:
inner(node.left, level + 1)
if node.right:
inner(node.right, level + 1)
inner(root, 0)
return res
if __name__ == "__main__":
arr = [3, 9, 20, None, None, 15, 7]
root = create_tree(arr)
res = Solution().zigzagLevelOrder(root)
print res