题目描述
You are given two positive integers $\class{ML__boldsymbol}{\boldsymbol{a}}$ and $\boldsymbol{b}$ in binary representation. You should find the following sum modulo $10^9+7$:
$\sum\limits_{i=0}^{314159}\left(a\:x or\left(b\:s h l\:i\right)\right)$
where operation $\boldsymbol{x}\textbf{or}$ means exclusive OR operation, operation $\mbox{shl}$ means binary shift to the left.
Please note, that we consider ideal model of binary integers. That is there is infinite number of bits in each number, and there are no disappearings (or cyclic shifts) of bits.
Input Format
The first line contains number $\class{ML__boldsymbol}{\boldsymbol{a}}$ $(1\leq a<2^{10^{5}})$ in binary representation. The second line contains number $\boldsymbol{b}$ $(1\leq b<2^{10^{5}})$ in the same format. All the numbers do not contain leading zeros.
Output Format
Output a single integer $-$ the required sum modulo $10^9+7$.
Sample Input
10
1010
Sample Output
489429555
输入格式
见题面
输出格式
见题面