From 11187c2700cae65629e0233c7b18496f68ff5ea1 Mon Sep 17 00:00:00 2001
From: Matej Focko <mfocko@redhat.com>
Date: Fri, 8 Dec 2023 22:19:37 +0100
Subject: [PATCH] =?UTF-8?q?problems(swift):=20add=20=E2=80=9C606.=20Constr?=
 =?UTF-8?q?uct=20String=20from=20Binary=20Tree=E2=80=9D?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
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Signed-off-by: Matej Focko <mfocko@redhat.com>
---
 .../construct-string-from-binary-tree.swift   | 37 +++++++++++++++++++
 1 file changed, 37 insertions(+)
 create mode 100644 problems/swift/construct-string-from-binary-tree.swift

diff --git a/problems/swift/construct-string-from-binary-tree.swift b/problems/swift/construct-string-from-binary-tree.swift
new file mode 100644
index 0000000..d5c459b
--- /dev/null
+++ b/problems/swift/construct-string-from-binary-tree.swift
@@ -0,0 +1,37 @@
+/**
+ * Definition for a binary tree node.
+ * public class TreeNode {
+ *     public var val: Int
+ *     public var left: TreeNode?
+ *     public var right: TreeNode?
+ *     public init() { self.val = 0; self.left = nil; self.right = nil; }
+ *     public init(_ val: Int) { self.val = val; self.left = nil; self.right = nil; }
+ *     public init(_ val: Int, _ left: TreeNode?, _ right: TreeNode?) {
+ *         self.val = val
+ *         self.left = left
+ *         self.right = right
+ *     }
+ * }
+ */
+class Solution {
+    func tree2str(_ root: TreeNode?) -> String {
+        if let root = root {
+            let left = tree2str(root.left)
+            let right = tree2str(root.right)
+
+            var l = ""
+            if left != "" || right != "" {
+                l = "(\(left))"
+            }
+
+            var r = ""
+            if right != "" {
+                r = "(\(right))"
+            }
+
+            return "\(root.val)\(l)\(r)"
+        }
+
+        return ""
+    }
+}