public void CheckStraightLineTest()
        {
            var s = new Solution();

            int[][] coordinates;

            coordinates = Create2dArray(2, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7);
            Assert.True(s.CheckStraightLine(coordinates));

            coordinates = Create2dArray(2, 1, 1, 2, 2, 3, 4, 4, 5, 5, 6, 7, 7);
            Assert.False(s.CheckStraightLine(coordinates));
        }