Golang | Leetcode Golang题解之第538题把二叉搜索树转换为累加树
题目：
题解：
func getSuccessor(node *TreeNode) *TreeNode {
succ := node.Right
for succ.Left != nil && succ.Left != node {
succ = succ.Left
}
return succ
}
func convertBST(root *TreeNode) *TreeNode {
sum := 0
node := root
for node != nil {
if node.Right == nil {
sum += node.Val
node.Val = sum
node = node.Left
} else {
succ := getSuccessor(node)
if succ.Left == nil {
succ.Left = node
node = node.Right
} else {
succ.Left = nil
sum += node.Val
node.Val = sum
node = node.Left
}
}
}
return root
}