public void SummingMatrices_CorrectParams_ExpectedResult()
{
int[,] arr1 = { { 1, 2 }, { 2, 4 } };
SymmetricMatrix <int> m1 = new SymmetricMatrix <int>(arr1);
int[,] arr2 = { { 1, 2, 3 }, { 1, 2, 3 }, { 1, 2, 3 } };
SquareMatrix <int> m2 = new SquareMatrix <int>(arr2);
Matrix <int> matrix = m1.SumMatrices(m2);
int expected = 6;
int actual = matrix[1, 1];
Assert.AreEqual(expected, actual);
}