diff --git a/144-binary-tree-preorder-traversal/README.md b/144-binary-tree-preorder-traversal/README.md new file mode 100644 index 0000000..320ded4 --- /dev/null +++ b/144-binary-tree-preorder-traversal/README.md @@ -0,0 +1,32 @@ +
Given the root of a binary tree, return the preorder traversal of its nodes' values.
+
Example 1:
+
+Input: root = [1,null,2,3] +Output: [1,2,3] ++ +
Example 2:
+ +Input: root = [] +Output: [] ++ +
Example 3:
+ +Input: root = [1] +Output: [1] ++ +
+
Constraints:
+ +[0, 100].-100 <= Node.val <= 100+
Follow up: Recursive solution is trivial, could you do it iteratively?
+