Working with Graphs & Trees

What tree traversal order does this implementation produce?

function dfs(root) {
  if (!root) return [];
  const result = [];
  const stack = [root];
  
  while (stack.length) {
    const current = stack.pop();
    result.push(current.value);
    if (current.right) stack.push(current.right);
    if (current.left) stack.push(current.left);
  }
  return result;
}

Level-order traversal
Inorder traversal
Preorder traversal
This implements preorder traversal because: 1) Processes current node before children (pre-order), 2) Uses stack for iterative implementation, 3) Visits root, then left subtree, then right subtree, 4) Pushes right child first to process left child first, 5) Maintains depth-first search characteristics, 6) Produces same result as recursive preorder traversal, 7) Useful for creating copy of tree or expression parsing, 8) Common pattern in tree serialization.
Postorder traversal

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