Text format: Binary Matrix
Problem Statement:
A matrix is called binary if all its elements are either 0 or 1.
Ecrade calls a binary matrix good if the following two properties hold:
- The bitwise XOR of all numbers in each row of the matrix is equal to 0.
- The bitwise XOR of all numbers in each column of the matrix is equal to 0.
Ecrade has a binary matrix of size n × m. He is interested in finding the minimum number of elements that need to be changed for the matrix to become good.
Input:
Each test contains multiple test cases.
The first line contains the number of test cases t (1 ≤ t ≤ 400).
The first line of each test case contains two integers n, m (1 ≤ n, m ≤ 100).
This is followed by n lines, each containing exactly m characters (0 or 1), describing the elements of Ecrade's matrix.
It is guaranteed that the sum of n * m across all test cases does not exceed 5 × 10⁴.
Output:
For each test case, output a single integer:
The minimum number of elements that need to be changed.
