add new solutions

solutions/1/q106/solution.go

@@ -0,0 +1,26 @@
+package q106
+
+import "slices"
+
+type TreeNode struct {
+	Val   int
+	Left  *TreeNode
+	Right *TreeNode
+}
+
+func buildTree(inorder []int, postorder []int) *TreeNode {
+	if len(inorder) == 0 {
+		return nil
+	}
+
+	val := postorder[len(postorder)-1]
+	pos := slices.Index(inorder, val)
+
+	return &TreeNode{
+		Val:   val,
+		Left:  buildTree(inorder[0:pos], postorder[:pos]),
+		Right: buildTree(inorder[pos+1:], postorder[pos:len(postorder)-1]),
+	}
+}
+
+var _ = buildTree