Ehab has an array $*a*$ of $*n*$ integers. He likes the bitwise-xor operation and he likes to bother Mahmoud so he came up with a problem. He gave Mahmoud $*q*$ queries. In each of them, he gave Mahmoud 2 integers $*l*$ and $*x*$, and asked him to find the number of subsequences of the first $*l*$ elements of the array such that their bitwise-xor sum is $*x*$. Can you help Mahmoud answer the queries?
A subsequence can contain elements that are not neighboring.
Input
The first line contains integers $*n*$ and $*q*$ $(1 ≤ *n*, *q* ≤ 10^{5})$, the number of elements in the array and the number of queries.
The next line contains $*n*$ integers $*a*_{1}$, $*a*_{2}$, $...$, $*a*_{*n*}$ $(0 ≤ *a*_{*i*} < 2^{20})$, the elements of the array.
The next $*q*$ lines, each contains integers $*l*$ and $*x*$ $(1 ≤ *l* ≤ *n*$, $0 ≤ *x* < 2^{20})$, representing the queries.
Output
For each query, output its answer modulo $10^{9} + 7$ in a newline.
Note
The bitwise-xor sum of the empty set is 0 and the bitwise-xor sum of a set containing one element is that element itself.
样例
5 5
0 1 2 3 4
4 3
2 0
3 7
5 7
5 8
4
2
0
4
0
3 2
1 1 1
3 1
2 0
4
2
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