First Tree-Question

Author: samyam81

June25/BSTtoGST.go

@@ -0,0 +1,27 @@
+package main
+
+type TreeNode struct {
+ Val int
+ Left *TreeNode
+ Right *TreeNode
+}
+
+func bstToGst(root *TreeNode) *TreeNode {
+sum := 0
+var dfs func(node *TreeNode)
+dfs = func(node *TreeNode) {
+if node == nil {
+return
+}
+// Traverse right subtree first
+dfs(node.Right)
+// Update sum and node value
+sum += node.Val
+node.Val = sum
+// Traverse left subtree
+dfs(node.Left)
+}
+
+dfs(root)
+return root
+}