min_val = root.val
m = 12345678190000
second = m
def dfs(root):
nonlocal second
if root is None:
return
if root.val > min_val:
second = min(second, root.val)
else:
dfs(root.left)
dfs(root.right)
dfs(root)
return second if second != m else -1
sl = Solution()
root = '[2,2,5,null,null,5,7]'
root = '[2,2,2]'
root = '[1,1,3,1,1,3,4,3,1,1,1,3,8,4,8,3,3,1,6,2,1]'
root = '[2,2,3]'
root = TreeNode.fromStrList(root)
TreeNode.travel(root)
print(sl.findSecondMinimumValue(root))
class Solution:
def increasingBST(self, root: TreeNode) -> TreeNode:
out = None
pre = None
def midorder(root):
if root is None:
return
midorder(root.left)
nonlocal pre
root.left = None
if pre is not None:
pre.right = root
else:
nonlocal out
out = root
pre = root
midorder(root.right)
midorder(root)
return out
inp = '[2,1,4,null,null,3]'
root = TreeNode.fromStrList(inp)
sl = Solution()
out = sl.increasingBST(root)
TreeNode.travel(out)