public bool Solve(int part = 0)
{
string[] towerSpecs = File.ReadAllLines("Day07/input.txt");
Dictionary <string, Tower> towers = new Dictionary <string, Tower>();
Regex regex = new Regex(@"^(\w+) \((\d+)\)\s?(-> ([\w\s,]+))?$");
Tower GetTower(string name)
{
if (towers.TryGetValue(name, out Tower t))
{
return(t);
}
else
{
var newTower = new Tower(name);
towers.Add(name, newTower);
return(newTower);
}
}
foreach (string spec in towerSpecs)
{
Match m = regex.Match(spec);
var tower = GetTower(m.Groups[1].Value);
tower.Weight = int.Parse(m.Groups[2].Value);
if (m.Groups[4].Success)
{
foreach (var subTowerName in m.Groups[4].Value.Split(", "))
{
tower.AddSubtower(GetTower(subTowerName));
}
}
}
var bottomTower = towers.Values.First(t => t.SubTowers.Count > 0 && !t.HasParent);
if (part == 2)
{
var faultyTower = bottomTower;
while (faultyTower != null)
{
var unbalancedSubTower = faultyTower.SubTowers.FirstOrDefault(t => !t.IsBalanced);
if (unbalancedSubTower == null)
{
var weightGroups =
from sub in faultyTower.SubTowers
group sub by sub.GetCombinedWeight() into g
select g;
int correctWeight = weightGroups.Where(g => g.Count() > 1).Select(g => g.Key).First();
var wrongWeightTower = weightGroups.First(g => g.Count() == 1).First();
int weightDiff = wrongWeightTower.GetCombinedWeight() - correctWeight;
Console.WriteLine($"{wrongWeightTower.Name} weight is {wrongWeightTower.Weight}, should be {wrongWeightTower.Weight - weightDiff}");
}
faultyTower = unbalancedSubTower;
}
}
else
{
Console.WriteLine(bottomTower.Name);
}
return(true);
}
public Tower(string Name, Tower Parent)
{
this.Name = Name;
this.Parent = Parent;
SubTowers = new List <Tower>();
}
public void AddSubtower(Tower subtower)
{
subtower.HasParent = true;
_subtowers.Add(subtower);
}