/// <summary>
/// Gets the number of unique houses that Santa delivers at least one present to.
/// </summary>
/// <param name="instructions">The instructions Santa should follow.</param>
/// <returns>The number of unique houses that receive a delivery of at least one present.</returns>
internal static int GetUniqueHousesVisitedBySanta(string instructions)
{
var directions = GetDirections(instructions);
var santa = new SantaGps();
var coordinates = new HashSet <Point>();
foreach (var direction in directions)
{
coordinates.Add(santa.Location);
santa.Move(direction);
}
return(coordinates.Count);
}
/// <summary>
/// Gets the number of unique houses that Santa delivers at least one present to.
/// </summary>
/// <param name="instructions">The instructions Santa should follow.</param>
/// <returns>The number of unique houses that receive a delivery of at least one present.</returns>
internal static int GetUniqueHousesVisitedBySanta(string instructions)
{
ICollection<CardinalDirection> directions = GetDirections(instructions);
var santa = new SantaGps();
var coordinates = new List<Point>();
foreach (var direction in directions)
{
if (!coordinates.Contains(santa.Location))
{
coordinates.Add(santa.Location);
}
santa.Move(direction);
}
return coordinates.Count;
}
/// <summary>
/// Gets the number of unique houses that Santa and Robo-Santa deliver at least one present to.
/// </summary>
/// <param name="instructions">The instructions that Santa and Robo-Santa should follow.</param>
/// <returns>The number of unique houses that receive a delivery of at least one present.</returns>
internal static int GetUniqueHousesVisitedBySantaAndRoboSanta(string instructions)
{
ICollection<CardinalDirection> directions = GetDirections(instructions);
var santa = new SantaGps();
var roboSanta = new SantaGps();
var current = santa;
var coordinates = new List<Point>();
foreach (var direction in directions)
{
current.Move(direction);
if (current.Location != Point.Empty && !coordinates.Contains(current.Location))
{
coordinates.Add(current.Location);
}
current = current == santa ? roboSanta : santa;
}
return coordinates.Count + 1;
}
/// <summary>
/// Gets the number of unique houses that Santa and Robo-Santa deliver at least one present to.
/// </summary>
/// <param name="instructions">The instructions that Santa and Robo-Santa should follow.</param>
/// <returns>The number of unique houses that receive a delivery of at least one present.</returns>
internal static int GetUniqueHousesVisitedBySantaAndRoboSanta(string instructions)
{
var directions = GetDirections(instructions);
var santa = new SantaGps();
var roboSanta = new SantaGps();
var current = santa;
var coordinates = new HashSet <Point>();
foreach (var direction in directions)
{
current.Move(direction);
if (current.Location != Point.Empty)
{
coordinates.Add(current.Location);
}
current = current == santa ? roboSanta : santa;
}
return(coordinates.Count + 1);
}