aoc/AdventOfCode/TwentyTwenty/Four.cs

using AdventOfCode.Contracts;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text.RegularExpressions;

namespace AoC.TwentyTwenty
{
    namespace AoC.TwentyTwenty
    {
        class Four : Day
        {
            public override int Year => 2020;
            public override int DayNumber => 4;

            public override void BigBoi(string[] input)
            {
                throw new NotImplementedException();
            }

            public override void Part1(string[] input)
            {
                IEnumerable<string> inputbutforreal = input.ToList();
                inputbutforreal = inputbutforreal.Append("");
                HashSet<string> keys = new HashSet<string>();
                int valid = 0;

                foreach (string s in inputbutforreal)
                {
                    if (s == string.Empty)
                    {
                        if (keys.Count == 7 && !keys.Contains("cid") || keys.Count > 7)
                        {
                            valid += 1;
                        }

                        keys = new HashSet<string>();
                        continue;
                    }

                    keys.Add(s.Split(":")[0]);
                }

                Print("1", valid);
            }

            public override void Part2(string[] input)
            {
                IEnumerable<string> inputbutforreal = input.ToList();
                inputbutforreal = inputbutforreal.Append("");
                HashSet<string> keys = new HashSet<string>();

                int valid = 0;
                bool isValid = true;

                foreach (string s in inputbutforreal)
                {
                    if (s == string.Empty)
                    {
                        if (isValid && (keys.Count == 7 && !keys.Contains("cid") || keys.Count > 7))
                        {
                            valid += 1;
                        }

                        isValid = true;
                        keys = new HashSet<string>();
                        continue;
                    }

                    if (!isValid)
                    {
                        continue;
                    }

                    string key = s.Split(":")[0];
                    string value = s.Split(":")[1];

                    isValid = key switch
                    {
                        "byr" => Regex.IsMatch(value, "19([2-9][0-9])|200[0-2]"),
                        "iyr" => Regex.IsMatch(value, "20(1[0-9]|20)"),
                        "eyr" => Regex.IsMatch(value, "20(2[0-9]|30)"),
                        "hgt" => Regex.IsMatch(value, "^(1([5-8][0-9]|9[0-3])cm|(59|6[0-9]|7[0-3])in)$"),
                        "hcl" => Regex.IsMatch(value, "#[0-9a-f]{6}"),
                        "ecl" => Regex.IsMatch(value, "amb|blu|brn|gry|grn|hzl|oth"),
                        "pid" => Regex.IsMatch(value, "^\\d{9}$"),
                        "cid" => true,
                        _ => throw new Exception("NIGGERS")
                    };



                    if (key == "pid" && !Regex.IsMatch(value, "^\\d{9}$") && Regex.IsMatch(value, "\\d{9}"))
                    {
                        Console.WriteLine(value);
                    }

                    keys.Add(key);
                }

                Print("2", valid);
            }
        }
    }
}