Given an array **arr[]** consisting of **0’s** and **1’s**. A flip operation is one in which you turn 1 into 0 and a 0 into 1.You have to do atmost one “Flip” operation of a subarray. Then finally display maximum number of 1 you can have in the array.

**Input:**

The first line of input consist of a single integer **T** denoting the total number of test case. First line of test case contains an integer N size of array. Second line of test case contains N space separated integers denoting the array arr[].

**Output:**

For each test case output a single integer representing the maximum number of 1's you can have in the array after atmost one flip operation.

**Constraints:**

1 <= T = 100

1 <= N <= 10^{4}

0 <= arr[i] <= 1

**Example:
Input:**

1

5

1 0 0 1 0

**Output:**

4

**Explanation:**

We can perform a flip operation in the range [1,2]

After flip operation array is : 1 1 1 1 0

Author: pra1nay7_313

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