public static long BagsContained(Bag bag)
{
return(bag.children.Select(x => x.Value * (BagsContained(x.Key) + 1)).Sum());
}
static void Main(string[] args)
{
var bagsRegex = new Regex(@"(?:(?<container>.+)\sbags\scontain\s)(?:(?<content>(?:(?<count>\d+)\s+)*(?<name>.+?))\sbag(?:s*)(?:,\s|\.))+", RegexOptions.Compiled);
var items = File.ReadLines("input.txt");
Dictionary <string, Bag> bags = new Dictionary <string, Bag>();
foreach (var item in items)
{
var match = bagsRegex.Match(item);
if (!match.Success)
{
throw new Exception("error parsing for " + item);
}
if (!bags.TryGetValue(match.Groups["container"].Value, out var container))
{
container = new Bag {
Name = match.Groups["container"].Value
};
bags.Add(container.Name, container);
}
if (match.Groups["name"].Value == "no other")
{
continue;
}
for (var i = 0; i < match.Groups["name"].Captures.Count; i++)
{
var name = match.Groups["name"].Captures[i].Value;
var count = int.Parse(match.Groups["count"].Captures[i].Value);
if (!bags.TryGetValue(name, out var bag))
{
bag = new Bag {
Name = name
};
bags.Add(bag.Name, bag);
}
bag.Containers.Add(container);
container.Bags.Add(name, count);
}
}
var gold = bags["shiny gold"];
var distinctBags = new HashSet <Bag>();
void CountUniqContainers(Bag b)
{
foreach (var c in b.Containers)
{
distinctBags.Add(c);
CountUniqContainers(c);
}
}
CountUniqContainers(gold);
Console.WriteLine("answer #1: " + distinctBags.Count);
int CountBags(Bag b)
{
var total = 0;
foreach (var(name, count) in b.Bags)
{
total += count + CountBags(bags[name]) * count;
}
return(total);
}
Console.WriteLine("answer #2: " + CountBags(gold));
}
public static bool CanContain(Bag bag, Bag inside)
{
return(bag.children.Where(x => x.Key == inside || CanContain(x.Key, inside)).Count() > 0);
}