private static int Parse1(IEnumerable <string> input)
{
var foods = new List <Food>();
var allIngridients = new HashSet <string>();
var allAllergens = new HashSet <string>();
var ingredientToAllergen = new DefaultValueDictionary <string, HashSet <string> >(() => new HashSet <string>());
var allergensToIngredients = new DefaultValueDictionary <string, HashSet <string> >(() => new HashSet <string>());
foreach (var line in input)
{
var sp = line.Split("(contains");
var ingredients = sp[0].Trim().Split().ToList();
var allergens = sp[1][0..^ 1].Split(",").Select(x => x.Trim()).ToList();
public MemoryGame(string[] init)
{
this.init = init.Select(x => long.Parse(x)).ToArray();
this.mem = new DefaultValueDictionary <long, LastTwo>(() => new LastTwo());
}