LeetCode: Merge Two Binary Trees Solution

Approach

Create a joint node

Implementation

1var mergeTrees = function (root1, root2) {
2  if (!root1) return root2
3  if (!root2) return root1
4
5  const root = new TreeNode(root1.val + root2.val)
6  root.left = mergeTrees(root1.left, root2.left)
7  root.right = mergeTrees(root1.right, root2.right)
8
9  return root
10}