1 typedef long long ll;
 2 class Solution
 3 {
 4     public:
 5         ll rnt = 0;
 6         void go(TreeNode* root,int val)
 7         {
 8             val = (val*2+root->val)%1000000007;
 9             if(root->left==NULL && root->right==NULL)
10             {
11                 rnt = (rnt+val)%1000000007;return ;
12             }
13             if(root->left)
14             go(root->left,val);
15             if(root->right)
16             go(root->right,val);
17         }
18         int sumRootToLeaf(TreeNode* root)
19         {
20             if(!root) return 0;
21             go(root,0);
22             return rnt;
23         }
24 };

没取余WA了两发，气死我了