public static T FirstOrDefault <T>(this IExtremaEnumerable <T> source)
{
if (source == null)
{
throw new ArgumentNullException(nameof(source));
}
return(source.Take(1).AsEnumerable().FirstOrDefault());
}
/// <summary>
/// Returns the only element of a sequence, and throws an exception if
/// there is not exactly one element in the sequence.
/// </summary>
/// <typeparam name="T">
/// The type of the elements of <paramref name="source"/>.</typeparam>
/// <param name="source">The input sequence.</param>
/// <exception cref="InvalidOperationException">
/// The input sequence contains more than one element.</exception>
/// <returns>
/// The single element of the input sequence.
/// </returns>
public static T Single <T>(this IExtremaEnumerable <T> source)
{
if (source == null)
{
throw new ArgumentNullException(nameof(source));
}
return(source.Take(2).AsEnumerable().Single());
}
public Group FindClosestGroup(Vector2 point, float size)
{
float Selector(Group group)
{
var groupCenter = group.Center;
float distance = Vector3.SqrMagnitude(point - groupCenter);
return(distance);
}
IExtremaEnumerable <Group> mins = _groups.MinBy(Selector);
var closestGroup = mins.First();
return(closestGroup);
}
public string SolvePart1()
{
var currentLocation = new Location(0, 0);
while (currentLocation.X <= XBoundary && currentLocation.Y <= YBoundary)
{
Dictionary <Location, int> distances = AllLocations.ToDictionary(location => location,
location => CalculateManhattanDistance(currentLocation, location));
IExtremaEnumerable <KeyValuePair <Location, int> >?sortedDistances = distances.MinBy(d => d.Value);
KeyValuePair <Location, int> shortestDistance = sortedDistances.First();
if (sortedDistances.Count() == 1 || sortedDistances.Count(s => s.Value == shortestDistance.Value) == 1)
{
// Only add if the current location is closest to a single point.
var newLocation = new Location(currentLocation.X, currentLocation.Y)
{
IsInfinite = currentLocation.X == 0 || currentLocation.Y == 0 ||
currentLocation.X == XBoundary || currentLocation.Y == YBoundary
};
AllLocations.SingleOrDefault(l => l == shortestDistance.Key)?.ClosestLocations.Add(newLocation);
}
// Move to the next location
if (currentLocation.Y == YBoundary)
{
currentLocation.X++;
currentLocation.Y = 0;
}
else
{
currentLocation.Y++;
}
}
List <Location> nonInfiniteLocations = AllLocations.Where(l => l.ClosestLocations.All(c => !c.IsInfinite)).ToList();
Location? largestNonInfinite = nonInfiniteLocations.MaxBy(l => l.ClosestLocations.Count).First();
return($"Part 1: {largestNonInfinite.ClosestLocations.Count}");
}