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Time Limit: 1 s Memory Limit: 1024 MB Total points: 100

#10352. Sequence Counting

Statistics

Given a sequence $\{a_0, a_1, \cdots, a_{n - 1}\}$ consisting only of 0s and 1s, find the number of sequences $\{b_0, b_1, \cdots, b_{m - 1}\}$ of length $m$ (where $1 \le m \le n$) consisting only of 0s and 1s, such that for all $0 \le p \le n - m$, the sum $\sum_{k = 0} ^ {m - 1}{a_{p + k} \wedge b_k}$ is even.

The answer should be taken modulo $1\,000\,000\,007$.

Input

A single 01 string representing the sequence $a$, where the $k$-th character from the left represents $a_k$.

Output

A single integer representing the number of sequences $b$ modulo $1\,000\,000\,007$.

Examples

Input 1

00101110101110101011

Output 1

699063

Input 2

00001100100101110011110011100010011010101011001010

Output 2

932640914

Constraints

The constraints for each test case are as follows:

Test Case ID $n$
1$n \le 20$
2
3$n \le 100$
4
5
6
7$n \le 5000$
8
9
10
11
12
13$n \le 50000$
14
15
16
17
18
19
20

For all test cases, $1 \le n \le 50000$, and the input is a 01 string.

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