Read problems statements in [Mandarin Chinese], [Russian], and [Bengali] as well.

You are given an array $A$ with $N$ integers. An array's score is defined as the bitwise AND of all its elements. You need to find the bitwise OR of the scores of all possible non-empty subarrays of $A$.

Furthermore, there are $Q$ queries. Each query consists of two integers $X$ and $V$. You need to change the value of the element at index $X$ to $V$. After each query, you again need to find the bitwise OR of the scores of all possible non-empty subarrays.

See the example for more clarification.

------ Input: ------
The first line of the input contains a single integer $T$ - the number of test cases. The description of $T$ test cases follows.

The first line of each test case contains two space-separated integers $N$ and $Q$ - the size of the array and the number of queries, respectively.

The second line contains $N$ space-separated integers $A_{1},\ldots,A_{N}$.

Each of the next $Q$ lines contains two space-separated integers $X$ and $V$ - the position and the new value of the query, respectively.

------ Output: ------
For each test case print $Q+1$ lines. In the first line print the answer for the original array and in the next $Q$ lines print the answer after every query.

------ Constraints ------
$1 ≤ T ≤ 100$

$1 ≤ N, Q ≤ 10^{5}$

$0 ≤ A_{i} ≤ 2^{31}-1$

$1 ≤ X ≤ N$

$0 ≤ V ≤ 2^{31}-1$

The sum of $N$ over all test cases does not exceed $10^{5}$

The sum of $Q$ over all test cases does not exceed $10^{5}$

----- Sample Input 1 ------
2
3 2
1 2 3
1 4
3 0
4 1
1 2 3 4
4 0
----- Sample Output 1 ------
3
7
6
7
3
----- explanation 1 ------
Example case 1: For the original array, all possible subarrays and their scores are as follows.

$AND(1) = 1$, $AND(2) = 2$, $AND(3) = 3$, $AND(1,2) = 0$, $AND(2,3) = 2$, $AND(1,2,3) = 0$.

The bitwise OR of all possible subarray's score is $OR(1,2,3,0,2,0) = 3$.

After the first query new array will be $[4,2,3]$ and the answer will be $7$.

After the second query new array will be $[4,2,0]$ and the answer will be $6$.

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