题解 | #合并二叉树#

/**
 * struct TreeNode {
 *	int val;
 *	struct TreeNode *left;
 *	struct TreeNode *right;
 * };
 */

class Solution {
public:
    /**
     * 
     * @param t1 TreeNode类 
     * @param t2 TreeNode类 
     * @return TreeNode类
     */
    TreeNode* mergeTrees(TreeNode* t1, TreeNode* t2) {
        // write code here
        if(t1 == nullptr && t2 == nullptr){
            return nullptr;
        }
        if(t1 == nullptr || t2 == nullptr){
            return t1 == nullptr ? t2 : t1;
        }
        
        TreeNode* root = new TreeNode(0);
        root->val = t1->val + t2->val;
        
        root->left = mergeTrees(t1->left, t2->left);
        root->right = mergeTrees(t1->right, t2->right);
        
        return root;
        
        
    }
};