public void MultiplyTreeCountsTest()
        {
            // Arrange
            var screenBuffer = new ScreenBuffer(_input);
            var routePlanner = new RoutePlanner(screenBuffer);

            var slopes = new[]
            {
                new SlopeModel {
                    Right = 1, Down = 1
                },
                new SlopeModel {
                    Right = 3, Down = 1
                },
                new SlopeModel {
                    Right = 5, Down = 1
                },
                new SlopeModel {
                    Right = 7, Down = 1
                },
                new SlopeModel {
                    Right = 1, Down = 2
                },
            };

            // Act
            var treeCount = routePlanner.MultiplyTreeCounts(slopes);

            // Assert
            Assert.That(treeCount, Is.EqualTo(336));
        }