#D7651. XOR Partitioning

    ID: 6360 Type: Default 2000ms 1073MiB

XOR Partitioning

XOR Partitioning

The beauty of a sequence a of length n is defined as a_1 \oplus \cdots \oplus a_n, where \oplus denotes the bitwise exclusive or (XOR).

You are given a sequence A of length N. Snuke will insert zero or more partitions in A to divide it into some number of non-empty contiguous subsequences.

There are 2^{N-1} possible ways to insert partitions. How many of them divide A into sequences whose beauties are all equal? Find this count modulo 10^{9}+7.

Constraints

  • All values in input are integers.
  • 1 \leq N \leq 5 \times 10^5
  • 0 \leq A_i < 2^{20}

Input

Input is given from Standard Input in the following format:

N A_1 A_2 \ldots A_{N}

Output

Print the answer.

Examples

Input

3 1 2 3

Output

3

Input

3 1 2 2

Output

1

Input

32 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Output

147483634

Input

24 1 2 5 3 3 6 1 1 8 8 0 3 3 4 6 6 4 0 7 2 5 4 6 2

Output

292

inputFormat

input are integers.

  • 1 \leq N \leq 5 \times 10^5
  • 0 \leq A_i < 2^{20}

Input

Input is given from Standard Input in the following format:

N A_1 A_2 \ldots A_{N}

outputFormat

Output

Print the answer.

Examples

Input

3 1 2 3

Output

3

Input

3 1 2 2

Output

1

Input

32 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Output

147483634

Input

24 1 2 5 3 3 6 1 1 8 8 0 3 3 4 6 6 4 0 7 2 5 4 6 2

Output

292

样例

32
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
147483634