multiply matrices in csharp

main.cs
public static double[,] MatrixMultiplication(double[,] matrix1, double[,] matrix2)
{
    int rows1 = matrix1.GetLength(0);
    int cols1 = matrix1.GetLength(1);
    int rows2 = matrix2.GetLength(0);
    int cols2 = matrix2.GetLength(1);

    if (cols1 != rows2)
    {
        throw new Exception("Matrices cannot be multiplied.");
    }

    double[,] result = new double[rows1, cols2];

    for (int i = 0; i < rows1; i++)
    {
        for (int j = 0; j < cols2; j++)
        {
            double sum = 0;

            for (int k = 0; k < cols1; k++)
            {
                sum += matrix1[i, k] * matrix2[k, j];
            }

            result[i, j] = sum;
        }
    }

    return result;
}
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main.cs
double[,] matrix1 = { { 1, 2 }, { 3, 4 } };
double[,] matrix2 = { { 5, 6 }, { 7, 8 } };
double[,] result = MatrixMultiplication(matrix1, matrix2);
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