diff --git a/two-sum-iv-input-is-a-bst/sol.go b/two-sum-iv-input-is-a-bst/sol.go
new file mode 100644
index 0000000..9405e04
--- /dev/null
+++ b/two-sum-iv-input-is-a-bst/sol.go
@@ -0,0 +1,31 @@
+package main
+
+type TreeNode struct {
+	Val   int
+	Left  *TreeNode
+	Right *TreeNode
+}
+
+/**
+ * Definition for a binary tree node.
+ * type TreeNode struct {
+ *     Val int
+ *     Left *TreeNode
+ *     Right *TreeNode
+ * }
+ */
+func search(node *TreeNode, k int, visited *map[int]bool) bool {
+	if node == nil {
+		return false
+	}
+	if _, ok := (*visited)[k-node.Val]; ok {
+		return true
+	}
+	(*visited)[node.Val] = true
+	return search(node.Left, k, visited) || search(node.Right, k, visited)
+}
+
+func findTarget(root *TreeNode, k int) bool {
+	visited := map[int]bool{}
+	return search(root, k, &visited)
+}