D - Meaningless Sequence

这是一道关于数学和位操作的编程题目。题目要求求解一个特定的数列的和模10^9 + 7,数列定义涉及到位运算AND。你需要计算从0到n的累计和并取模。

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https://codeforces.com/gym/102832/problem/D

Once there was a mathematician, who was obsessed with meaningless number sequences. Here is one of them.

 

an={1,c⋅max0≤i<nan&i,n=0otherwise,an={1,n=0c⋅max0≤i<nan&⁡i,otherwise,

where && denotes the bitwise AND operation.

As a mathematician, he could easily tell what anan was for any nn, but he wanted to test you. You are required to tell him

 

(∑i=0nai)mod(109+7)(∑i=0nai)mod(109+7)

to convince him that you have a deep understanding of this (although meaningless) sequence.

Input

The only line contains two integers nn and cc (0≤n<23000,0≤c≤109)0≤n<23000,0≤c≤109).

Specially, nn is given in binary presentation. cc is given in decimal presentation normally.

Output

Print what you are expected to tell the mathemat

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