Merge pull request neetcode-gh#924 from MaratKhakim/572-Subtree-Another

Kotlin: 572. Subtree of Another Tree

Author: Ahmad-A0

kotlin/572-Subtree-Of-Another-Tree.kt

@@ -0,0 +1,31 @@
+/**
+ * Example:
+ * var ti = TreeNode(5)
+ * var v = ti.`val`
+ * Definition for a binary tree node.
+ * class TreeNode(var `val`: Int) {
+ *     var left: TreeNode? = null
+ *     var right: TreeNode? = null
+ * }
+ */
+class Solution {
+    fun isSubtree(s: TreeNode?, t: TreeNode?): Boolean {
+        if (s == null)
+            return false
+
+        return equals(s, t) || isSubtree(s.left, t) || isSubtree(s.right, t);
+    }
+
+    fun equals(s: TreeNode?, t: TreeNode?): Boolean {
+        if (s == null && t == null)
+            return true;
+
+        if (s == null || t == null)
+            return false;
+
+        if (s.`val` != t.`val`)
+            return false;
+
+        return equals(s.left, t.left) && equals(s.right, t.right);
+    }
+}