题解 | #合并二叉树#

/**
 * struct TreeNode {
 *	int val;
 *	struct TreeNode *left;
 *	struct TreeNode *right;
 *	TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
 * };
 */
class Solution {
public:
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     * 
     * @param t1 TreeNode类 
     * @param t2 TreeNode类 
     * @return TreeNode类
     */
    TreeNode* mergeTrees(TreeNode* t1, TreeNode* t2) {
        if(not t1) return t2;
        auto merge = [](auto&& self, const auto& n1, const auto& n2) -> auto {
            if(not n1) return n2;
            if(not n2) return n1;
            n1->val += n2->val;
            n1->left = self(self, n1->left, n2->left);
            n1->right = self(self, n1->right, n2->right);
            return n1;
        };
        return merge(merge, t1, t2);
    }
};