AlgoDaily - Merge Two Binary Trees - Traversal Is The Key

Traversal is the key

Since we started we'll need to eventually return a merged root, let's go with an pre-order traversal. Pseudocode as follows:

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function preOrder(tree1, tree2) {
  if (tree1 == null) {
    return tree2;
  }
  if (tree2 == null) {
    return tree1;
  }
  return tree1.val + tree2.val;
​
  // Do the above on both of their left children
  preOrder(tree1.left, tree2.left)
​
  // Do the above on both of their right children
  preOrder(tree1.right, tree2.right)
}

OUTPUT

Results will appear here.