aoc 1+2

www/statics/aoc/2018/24_solution-2.linq

@@ -0,0 +1,148 @@
+<Query Kind="Program" />
+
+class ArmyGroup
+{
+	public string Source;
+	
+	public int UnitCount;
+	public int HitPoints;
+	public List<string> Weakness = new List<string>();
+	public List<string> Immunity = new List<string>();
+	public string DamageType;
+	public int DamageValue;
+	public int Initiative;
+
+	public int EffectivePower => UnitCount * DamageValue;
+	public bool Alive => UnitCount>0;
+	
+	public ArmyGroup NextTarget = null;
+	public bool IsTargeted = false;
+}
+
+void Main() => Enumerable.Range(0, int.MaxValue).Select(Calc).First(b=>b>0).Dump();
+
+int Calc(int boost)
+{
+	var groups = Load(File.ReadAllLines(Path.Combine(Path.GetDirectoryName(Util.CurrentQueryPath), @"24_input.txt")));
+
+	foreach(var g in groups.Where(p => p.Source=="ImmuneSystem")) g.DamageValue += boost;
+
+	for (int gen = 0; ; gen++)
+	{
+		if (!(groups.GroupBy(g => g.Source).All(g => g.Any(a => a.Alive)))) break;
+
+		bool dmg = Fight(groups);
+		
+		if (!dmg) return 0;
+	}
+
+	return groups.Where(p => p.Source=="ImmuneSystem").Sum(p => p.UnitCount) - groups.Where(p => p.Source=="Infection").Sum(p => p.UnitCount);
+}
+
+List<ArmyGroup> Load(string[] lines)
+{
+	return new[]
+	{
+		lines.Skip(1).TakeWhile(l => !string.IsNullOrWhiteSpace(l)).Select(l => LoadSingle("ImmuneSystem", l)),
+		lines.Skip(1).SkipWhile(l => !string.IsNullOrWhiteSpace(l)).Skip(2).Select(l => LoadSingle("Infection", l))
+	}
+	.SelectMany(p=>p)
+	.ToList();
+}
+
+ArmyGroup LoadSingle(string src, string line)
+{
+	var ag = new ArmyGroup { Source=src };
+
+	var i1 = line.IndexOf(' ');
+	ag.UnitCount = int.Parse(line.Substring(0, i1).Trim());
+	line = line.Substring(i1).Trim().Substring(15).Trim();
+
+	var i6 = line.IndexOf(' ');
+	ag.HitPoints = int.Parse(line.Substring(0, i6).Trim());
+	line = line.Substring(i6).Trim().Substring(11).Trim();
+	
+	var i2 = line.IndexOf(')');
+	if (i2 != -1)
+	{
+		var spec0 = line.Substring(1, i2).TrimEnd(')');
+		line = line.Substring(1).Substring(i2).Substring(1).Trim();
+
+		foreach (var spc in spec0.Split(';').Select(p => p.Trim()))
+		{
+			if (spc.StartsWith("weak to")) ag.Weakness.AddRange(spc.Substring("weak to".Length).Trim().Split(',').Select(p => p.Trim()));
+			if (spc.StartsWith("immune to")) ag.Immunity.AddRange(spc.Substring("immune to".Length).Trim().Split(',').Select(p => p.Trim()));
+		}
+	}
+	line = line.Substring(25).Trim();
+
+	var i3 = line.IndexOf(' ');
+	ag.DamageValue = int.Parse(line.Substring(0, i3).Trim());
+	line = line.Substring(i3).Trim().Trim();
+
+	var i4 = line.IndexOf(' ');
+	ag.DamageType = line.Substring(0, i4).Trim();
+	line = line.Substring(i4).Trim().Trim();
+
+	var i5 = line.LastIndexOf(' ');
+	ag.Initiative = int.Parse(line.Substring(i5).Trim());
+
+	return ag;
+}
+
+bool Fight(List<ArmyGroup> groups)
+{
+	// PHASE 1
+
+	foreach (var g in groups) { g.IsTargeted=false; g.NextTarget=null; }
+	
+	foreach (var g in groups.Where(g => g.Alive).OrderByDescending(g => g.EffectivePower).ThenByDescending(g => g.Initiative))
+	{
+		SelectTarget(g, groups);
+	}
+
+	// PHASE 2
+
+	bool d = false;
+
+	foreach (var g in groups.Where(g => g.Alive).OrderByDescending(g => g.Initiative).Where(g => g.NextTarget!=null))
+	{
+		var a = Attack(g, g.NextTarget);
+		if (a)d=true;
+	}
+	return d;
+}
+
+void SelectTarget(ArmyGroup att, List<ArmyGroup> groups)
+{
+	att.NextTarget = groups
+		.Where(g => g.Alive)
+		.Where(g => g.Source != att.Source)
+		.Where(g => !g.IsTargeted)
+		.Where(g => CalcFullDamage(att, g)>0)
+		.OrderByDescending(g => CalcFullDamage(att, g))
+		.ThenByDescending(g => g.EffectivePower)
+		.ThenByDescending(g => g.Initiative)
+		.FirstOrDefault();
+	if (att.NextTarget != null) att.NextTarget.IsTargeted = true;
+}
+
+int CalcFullDamage(ArmyGroup att, ArmyGroup def)
+{
+	if (att.UnitCount==0) return 0;
+
+	var dmg = att.EffectivePower;
+	if (def.Immunity.Contains(att.DamageType)) return 0;
+	if (def.Weakness.Contains(att.DamageType)) return dmg*2;
+	return dmg;
+}
+
+bool Attack(ArmyGroup att, ArmyGroup def)
+{
+	var dmg = CalcFullDamage(att, def);
+	var kill = (int)(dmg / def.HitPoints);
+	def.UnitCount -= kill;
+	if (def.UnitCount<0) def.UnitCount = 0;
+	return kill>0;
+	
+}