Flip Bits Problem Explanation

Given an array of integers ARR of size N, consisting of 0s and 1s, you need to select a sub-array and flip its bits. Your task is to return the maximum count of 1s that can be obtained by flipping a chosen sub-array at most once.

Input:

The input consists of a single integer T (number of test cases). For each test case:

• An integer N, representing the size of the array.
• An array of N space-separated integers representing the elements of the array.

Output:

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

Example:

Input:

T = 1
N = 5
ARR = [1, 1, 0, 0, 1]

Output:

5

Explanation:

By flipping the sub-array from index 2 to 3, the resulting array becomes [1, 1, 1, 1, 1], which contains five 1s. Hence, the output is 5.

Constraints:

• 1 <= T <= 100
• 1 <= N <= 10^4
• 0 <= ARR[i] <= 1

Note:

You are not required to print anything. Implement the given function to return the answer.