To verify whether the piglet is a reliable intermediate-level competitive programmer, Little L gives him the following problem.
Every positive integer $$$x$$$ can be uniquely written as $$$\overline{d_md_{m-1}\cdots d_0}$$$, satisfying all of the following conditions:
Given positive integers $$$L$$$ and $$$R$$$ ($$$L\le R$$$), compute $$$\left(\sum\limits_{i=L}^Rf(i)\right)\bmod(10^9+7)$$$.
The input consists of a single line containing two integers $$$L,R$$$ ($$$1\le L\le R\le10^{202512}$$$).
Output a single integer, the value of $$$\left(\sum\limits_{i=L}^Rf(i)\right)\bmod(10^9+7)$$$.
20249 20257
935315683
1 20252025202520252025
423849977
In the first example, only $$$20249$$$ is good, and $$$2025^{20249}\bmod(10^9+7)=935315683$$$.