Rough day 4 implementation

2020.csproj

@@ -16,6 +16,9 @@
     <None Update="03input.txt">
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </None>
+    <None Update="04input.txt">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </None>
   </ItemGroup>
 
 </Project>

Program.cs

@@ -7,6 +7,7 @@
          Q01.Go();
          Q02.Go();
          Q03.Go();
+         Q04.Go();
       }
    }
 }

Q04.cs

@@ -0,0 +1,145 @@
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.IO;
+using System.Text.RegularExpressions;
+
+namespace _2020
+{
+   class Q04
+   {
+      static List<Dictionary<string, string>> Passports = new List<Dictionary<string, string>>();
+
+      static Regex PassportRegex = new Regex(@"(?<key>[a-z]{3}):(?<val>\S+)", RegexOptions.Compiled);
+      static Regex HTMLColor = new Regex("^#[0-9a-f]{6}$", RegexOptions.Compiled);
+      static Regex PassportID = new Regex("^[0-9]{9}$", RegexOptions.Compiled);
+
+      public static void Go()
+      {
+         MakeList();
+         Part1();
+         Part2();
+      }
+
+      static void MakeList()
+      {
+         using var fs = new FileStream("04input.txt", FileMode.Open);
+         using var sr = new StreamReader(fs);
+         string line;
+         while ((line = sr.ReadLine()) != null)
+         {
+            if (line.Length == 0 || Passports.Count == 0)
+            {
+               Passports.Add(new Dictionary<string, string>());
+            }
+
+            var matches = PassportRegex.Matches(line);
+            for (int i = 0; i < matches.Count; i++)
+            {
+               Passports[Passports.Count - 1].Add(matches[i].Groups["key"].Value, matches[i].Groups["val"].Value);
+            }
+         }
+      }
+
+      static bool IsValid_Basic(Dictionary<string, string> passport)
+      {
+         if (passport.Count >= 8)
+         {
+            return true;
+         }
+         else if (passport.Count == 7 && !passport.ContainsKey("cid"))
+         {
+            return true;
+         }
+
+         return false;
+      }
+
+      static void Part1()
+      {
+         int numValid = 0;
+         foreach (var passport in Passports)
+         {
+            if (IsValid_Basic(passport))
+            {
+               numValid++;
+            }
+         }
+
+         Debug.WriteLine($"Q04Part1: num valid={numValid}");
+      }
+
+      static void Part2()
+      {
+         int numValid = 0;
+         foreach (var passport in Passports)
+         {
+            bool isValid = IsValid_Basic(passport);
+            foreach (var set in passport)
+            {
+               switch (set.Key)
+               {
+                  case "byr":
+                     {
+                        var year = Convert.ToInt32(set.Value);
+                        isValid = isValid && year >= 1920 && year <= 2002;
+                     }
+                     break;
+
+                  case "iyr":
+                     {
+                        var year = Convert.ToInt32(set.Value);
+                        isValid = isValid && year >= 2010 && year <= 2020;
+                     }
+                     break;
+
+                  case "eyr":
+                     {
+                        var year = Convert.ToInt32(set.Value);
+                        isValid = isValid && year >= 2020 && year <= 2030;
+                     }
+                     break;
+
+                  case "hgt":
+                     {
+                        var val = 0;
+                        var unit = "";
+                        if (set.Value.Length > 2)
+                        {
+                           val = Convert.ToInt32(set.Value[..^2]);
+                           unit = set.Value[^2..];
+                        }
+                        isValid = isValid && ((unit == "cm" && val >= 150 && val <= 193) || (unit == "in" && val >= 59 && val <= 76));
+                     }
+                     break;
+
+                  case "hcl":
+                     {
+                        isValid = isValid && HTMLColor.IsMatch(set.Value);
+                     }
+                     break;
+
+                  case "ecl":
+                     {
+                        isValid = isValid && (set.Value == "amb" || set.Value == "blu" || set.Value == "brn" || set.Value == "gry" || set.Value == "grn" || set.Value == "hzl" || set.Value == "oth");
+                     }
+                     break;
+
+                  case "pid":
+                     {
+                        isValid = isValid && PassportID.IsMatch(set.Value);
+                     }
+                     break;
+               }
+            }
+
+            if (isValid)
+            {
+               numValid++;
+            }
+         }
+
+         Debug.WriteLine($"Q04Part2: num valid={numValid}");
+      }
+   }
+}