题解 | #二叉树根节点到叶子节点的所有路径和#

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

class Solution {
public:
    /**
     * 
     * @param root TreeNode类 
     * @return int整型
     */
    int res = 0;
    void sn(TreeNode* root, int p) {
        // write code here
        if(!root){
            return;
        }
        if(root->left){
            sn(root->left, p*10 + root->val);
        }
        if(root->right){
            sn(root->right, p*10 + root->val);
        }
        if(!root->left&&!root->right){
            res += p*10 + root->val;
        }
        
    }
    int sumNumbers(TreeNode* root) {
        // write code here
        sn(root, 0);
        return res;
    }
};