938

1 files changed, 34 insertions, 0 deletions

diff --git a/938/main.go b/938/main.go
new file mode 100644
index 0000000..89c18d3
--- /dev/null
+++ b/938/main.go
@@ -0,0 +1,34 @@
+package main
+
+import "fmt"
+
+type TreeNode struct {
+	Val   int
+	Left  *TreeNode
+	Right *TreeNode
+}
+
+func preOrder(node *TreeNode, sum *int, low, high int) {
+	if node == nil {
+		return
+	}
+
+	if node.Val >= low && node.Val <= high {
+		*sum += node.Val
+	}
+
+	preOrder(node.Left, sum, low, high)
+	preOrder(node.Right, sum, low, high)
+}
+
+func rangeSumBST(root *TreeNode, low int, high int) int {
+	sum := 0
+
+	preOrder(root, &sum, low, high)
+
+	return sum
+}
+
+func main() {
+	fmt.Println("vim-go")
+}