---
category_name: medium
problem_code: INCXOR
problem_name: 'Increasing Xor Sequence'
languages_supported:
- ADA
- ASM
- BASH
- BF
- C
- 'C99 strict'
- CAML
- CLOJ
- CLPS
- 'CPP 4.3.2'
- 'CPP 4.9.2'
- CPP14
- CS2
- D
- ERL
- FORT
- FS
- GO
- HASK
- ICK
- ICON
- JAVA
- JS
- 'LISP clisp'
- 'LISP sbcl'
- LUA
- NEM
- NICE
- NODEJS
- 'PAS fpc'
- 'PAS gpc'
- PERL
- PERL6
- PHP
- PIKE
- PRLG
- PYPY
- PYTH
- 'PYTH 3.4'
- RUBY
- SCALA
- 'SCM chicken'
- 'SCM guile'
- 'SCM qobi'
- ST
- TCL
- TEXT
- WSPC
max_timelimit: '1'
source_sizelimit: '50000'
problem_author: lg5293
problem_tester: errichto
date_added: 13-03-2017
tags:
- bitmasks
- cook80
- digit
- lg5293
- medium
editorial_url: 'https://discuss.codechef.com/problems/INCXOR'
time:
view_start_date: 1489949100
submit_start_date: 1489949100
visible_start_date: 1489949100
end_date: 1735669800
current: 1493557919
layout: problem
---
All submissions for this problem are available.### Read problems statements in [Mandarin Chinese](http://www.codechef.com/download/translated/COOK80/mandarin/INCXOR.pdf), [Russian](http://www.codechef.com/download/translated/COOK80/russian/INCXOR.pdf) and [Vietnamese](http://www.codechef.com/download/translated/COOK80/vietnamese/INCXOR.pdf) as well.
You are given a sequence of **n** integers **a**1, ..., **a****n**. Count the number of sequences b = b1, ..., b**n** such that: 0 ≤ b1 ≤ ... ≤ b**n** 31 and (**a**1 XOR b1) ≤ … ≤ (**a****n** XOR b**n**). Return this count, modulo 109+7.
Here XOR denotes the [bitwise XOR](https://en.wikipedia.org/wiki/Bitwise_operation#XOR).
### Input
The first line of input will contain an integer **T**, the number of test cases.
Each test case will be in two lines.
The first line of the case will contain an integer **n**.
The next line of the case will contain **n** space separated integers **a**1,...,**a****n**.
### Output
Output a single number, the number of sequences, modulo 109+7.
### Constraints
- 1 ≤ **T** ≤ 100
- 1 ≤ **n** ≤ 5
- 0 ≤ **a**i 31
### Example
<pre>
<b>Input: </b>
4
1
42
5
5 4 3 2 1
4
1194533513 122420337 1448417648 120078455
3
31 2047 2147483647
<b>Output:</b>
147483634
986095186
0
468598063
</pre>### Explanation
In the first case, there are 231 possible sequences, so the answer is 231 modulo 109+7 = 147483634
For the second case, one possible example of a valid sequence is b = 9, 9, 18, 19, 32. We can check that this sequence is nondecreasing, and also, we have (**a**1 XOR b1) = 12, (**a**2 XOR b2) = 13, (**a**3 XOR b3) = 17, (**a**4 XOR b4) = 17, (**a**5 XOR b5) = 33, which is also nondecreasing.
For the third case, no sequences satisfy the conditions.