Problem A

Statement
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A. Binary Matrixtime limit per test1 secondmemory limit per test512 megabytesinputstandard inputoutputstandard outputA matrix is called binary if all its elements are either $$$0$$$ or $$$1$$$.Ecrade calls a binary matrix $$$A$$$ good if the following two properties hold:  The bitwise XOR of all numbers in each row of matrix $$$A$$$ is equal to $$$0$$$.  The bitwise XOR of all numbers in each column of matrix $$$A$$$ is equal to $$$0$$$. Ecrade has a binary matrix of size $$$n \cdot m$$$. He is interested in the minimum number of elements that need to be changed for the matrix to become good.However, it seems a little difficult, so please help him!InputEach test contains multiple test cases. The first line contains the number of test cases $$$t$$$ ($$$1 \le t \le 400$$$). The description of the test cases follows. The first line of each test case contains two integers $$$n, m$$$ ($$$1 \le n, m \le 100$$$).This is followed by $$$n$$$ lines, each containing exactly $$$m$$$ characters consisting only of $$$0$$$ and $$$1$$$, describing the elements of Ecrade's matrix.It is guaranteed that the sum of $$$n \cdot m$$$ across all test cases does not exceed $$$5 \cdot 10^4$$$.OutputFor each test case, output a single integer, the minimum number of elements that need to be changed.ExampleInput73 30101010103 30000000003 31000100013 31010100003 30000100001 401014 10101Output2
0
3
3
1
2
2
NoteIn the first test case, he needs to change 2 elements to obtain the following matrix $$$\begin{pmatrix}1&1&0\\1&0&1\\0&1&1\end{pmatrix}$$$.In the second test case, he can make no changes to obtain the following matrix $$$\begin{pmatrix}0&0&0\\0&0&0\\0&0&0\end{pmatrix}$$$.In the third test case, he needs to change 3 elements to obtain the following matrix $$$\begin{pmatrix}1&0&1\\0&0&0\\1&0&1\end{pmatrix}$$$.