Leetcode # 589. N-ary Tree Preorder Traversal

https://leetcode.com/problems/n-ary-tree-preorder-traversal/

Solution

Time Complexity: O(len(tree))
Space Complexity: O(len(tree))
(The input and output generally do not count towards the space complexity.)

class Solution:
  def preorder(self, root: 'Node') -> List[int]:
    stack = [root] if root is not None else []
    preorder_traversal = []
    while stack:
      cur = stack.pop()
      for node in cur.children[::-1]:
        stack.append(node)
      preorder_traversal.append(cur.val)
    return preorder_traversal

Last Updated on 2023/08/16 by A1go