public string Answer()
{
ReactionPerProduct = File.ReadAllLines("D14.txt").Select(s => Reaction.FromString(s)).ToDictionary(r => r.Product.ReactantName);
foreach (var r in ReactionPerProduct.Keys)
{
Storage[r] = 0;
}
var fuel = Maths.LongBinarySearch(0, (long)1e12, numFuel => {
OreRequired = 0;
ProduceReactantOrder(new ReactantOrder("FUEL", numFuel));
return(OreRequired > 1e12);
});
return(fuel.ToString());
}
public static void Main(string[] args)
{
var reactions = File.ReadAllText("input.txt").Split('\n').ToList().ConvertAll(a => Reaction.FromString(a));
var fuelReaction = reactions.Where(a => a.Output.Item2 == "FUEL").First();
//Console.WriteLine(string.Join("\n", reactions));
Console.WriteLine("\n\nFUEL reaction: " + fuelReaction);
var oreUsed = (long)0;
var fuelMade = (long)0;
var neededReactions = new List <Reaction>()
{
fuelReaction
};
var running = true;
var excess = new Dictionary <string, int>();
while (oreUsed < 1000000000000)
{
while (running)
{
var newReactions = new List <Reaction>();
foreach (var r in neededReactions)
{
foreach (var i in r.Inputs)
{
if (i.Item2 == "ORE")
{
oreUsed += i.Item1;
continue;
}
var quantityNeeded = i.Item1;
if (excess.ContainsKey(i.Item2))
{
quantityNeeded -= excess[i.Item2];
excess[i.Item2] = 0;
}
stillNeeded :;
if (quantityNeeded < 0)
{
if (excess.ContainsKey(i.Item2))
{
excess[i.Item2] = -quantityNeeded;
}
else
{
excess.Add(i.Item2, -quantityNeeded);
}
goto notNeeded;
}
if (quantityNeeded == 0)
{
goto notNeeded;
}
var r2 = reactions.Where(a => a.Output.Item2 == i.Item2).First();
newReactions.Add(r2);
quantityNeeded -= r2.Output.Item1;
if (quantityNeeded != 0)
{
goto stillNeeded;
}
notNeeded :;
}
}
neededReactions = newReactions;
running = neededReactions.Count > 0;
a :;
foreach (var e in excess)
{
if (e.Value == 0)
{
excess.Remove(e.Key); goto a;
}
}
//Console.WriteLine("\n\n\nOre Used: " + oreUsed + "\nNew list of needed reactions:\n" + string.Join("\n", neededReactions) + "\n\n" + "Excess: " + string.Join(", ", excess));
//Console.ReadLine();
}
neededReactions = new List <Reaction>()
{
fuelReaction
};
fuelMade++;
running = true;
Console.Title = string.Format("{0:n0}", oreUsed) + " : " + string.Format("{0:n0}", (fuelMade - 1));
}
Console.WriteLine(oreUsed + " : " + (fuelMade - 1));
Console.Read();
}
