private static long RunAlgorithm2(Day3Input input)
{
return(RunAlgorithm1(input, 1, 1) *
RunAlgorithm1(input, 3, 1) *
RunAlgorithm1(input, 5, 1) *
RunAlgorithm1(input, 7, 1) *
RunAlgorithm1(input, 1, 2));
}
private static long RunAlgorithm1(Day3Input input, int right, int down)
{
return(Positions(input.Width, right, down)
.TakeWhile(position => input.IsPositionValid(position))
.Count(position => input.TreeAt(position)));
}