617. Merge Two Binary Trees

https://leetcode.com/problems/merge-two-binary-trees/

Python

class Solution:
    def mergeTrees(self, root1: Optional[TreeNode], root2: Optional[TreeNode]) -> Optional[TreeNode]:
        if not root1 or not root2:
            return root1 if root1 else root2

        node = TreeNode(val=root1.val+root2.val)
        node.left = self.mergeTrees(root1.left, root2.left)
        node.right = self.mergeTrees(root1.right, root2.right)

        return node

Go

func mergeTrees(root1 *TreeNode, root2 *TreeNode) *TreeNode {
    if root1 == nil || root2 == nil {
        if root1 != nil {
            return root1
        } else {
            return root2
        }
    }

    node := new(TreeNode)
    node.Val = root1.Val + root2.Val
    node.Left = mergeTrees(root1.Left, root2.Left)
    node.Right = mergeTrees(root1.Right, root2.Right)

    return node
}