c++ - How to pass two dimensional array of an unknown size to a function

Question

I want to make class library, a function which its parameter is a matrix of unknown size, and the user will create his own matrix with his own size and pass it to this function to do some operations on his matrix like this, will be the function

calculateDeterminantOfTheMatrix( int matrix[][])
{
   some Operations to do on matrix 
}

Answer 1

Multi-dimensional arrays are not very well supported by the built-in components of C and C++. You can pass an N-dimension array only when you know N-1 dimensions at compile time:

calculateDeterminantOfTheMatrix( int matrix[][123])

However, the standard library supplies std::vector container, that works very well for multi-dimension arrays: in your case, passing vector<vector<int> > &matrix would be the proper way of dealing with the task in C++.

int calculateDeterminantOfTheMatrix(vector<vector<int> > &matrix) {
    int res = 0;
    for (int i = 0 ; i != matrix.size() ; i++)
        for(int j = 0 ; j != matrix[i].size() ; j++)
            res += matrix[i][j];
    return res;
}

As an added bonus, you wouldn't need to pass dimensions of the matrix to the function: matrix.size() represents the first dimension, and matrix[0].size() represents the second dimension.