The traversal itself isn't the hard part, simple DFS or BFS gets you there.
Start by clarifying the problem and defining the Node class with a value and a list of children. Then, discuss both recursive and iterative traversal strategies, highlighting trade-offs. Finally, implement the chosen solution, test with examples, and analyze time and space complexity.
Pro tip: Demonstrate awareness of recursion depth limits and propose an iterative solution using a stack or queue to avoid stack overflow for deep trees. Also, mention that the solution can be adapted for other aggregations like max or min.
Ask if the tree can be empty, if values are integers, and if the tree is large. Define the Node class with a constructor that initializes value and children list.
Decide between recursive DFS (simpler) and iterative BFS/DFS (avoids recursion limit). Explain the trade-offs and pick one based on constraints.
Write clean code for the chosen approach. For recursion, sum node value plus recursive calls on children. For iteration, use a stack or queue to traverse and accumulate sum.
Walk through a simple tree (e.g., root with two children) and an empty tree to verify correctness. Mention edge cases like single node or skewed tree.
State that time complexity is O(N) where N is number of nodes, and space complexity is O(H) for recursion (H is height) or O(W) for BFS (W is max width).
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.