leetcode-617. 合并二叉树

617. 合并二叉树 - 力扣（Leetcode）

递归合并二叉树 easy

/**
 * Definition for a binary tree node.
 * type TreeNode struct {
 *     Val int
 *     Left *TreeNode
 *     Right *TreeNode
 * }
 */
func mergeTrees(root1 *TreeNode, root2 *TreeNode) *TreeNode {
    if root1 != nil && root2 != nil {
        root1.Left = mergeTrees(root1.Left, root2.Left) 
        root1.Right = mergeTrees(root1.Right, root2.Right)
        root1.Val = root1.Val + root2.Val
    } else if root2 != nil {
        root1 = root2
    }

    return root1
}