[2023] Update Day1

Signed-off-by: TiagoRG <tiago.rgarcia@ua.pt>

Year2023/Day1.cs

@@ -2,80 +2,55 @@ namespace AdventOfCode.Year2023;
 
 public class Day1
 {
-    private static List<string> Input = File.ReadAllLines("inputs/Year2023/day1.txt").ToList();
-    private static int FirstNum;
-    private static int LastNum;
+    private static string[] Input = File.ReadAllLines("inputs/Year2023/day1.txt");
+
+    private static Dictionary<string, int> Part1Numbers = new Dictionary<string, int>() {
+        {"1", 1},
+        {"2", 2},
+        {"3", 3},
+        {"4", 4},
+        {"5", 5},
+        {"6", 6},
+        {"7", 7},
+        {"8", 8},
+        {"9", 9},
+    };
+
+    private static Dictionary<string, int> Part2Numbers = new Dictionary<string, int>(Part1Numbers) {
+        {"one", 1},
+        {"two", 2},
+        {"three", 3},
+        {"four", 4},
+        {"five", 5},
+        {"six", 6},
+        {"seven", 7},
+        {"eight", 8},
+        {"nine", 9},
+    };
 
     public static void Run()
     {
         Console.WriteLine($@"
 Day1 Solution
-Part1 Result: {Part1()}
-Part2 Result: {Part2()}
+Part1 Result: {Solve(Part1Numbers)}
+Part2 Result: {Solve(Part2Numbers)}
 
 =============================");
     }
 
-    private static int Part1()
+    private static int Solve(Dictionary<string, int> numbers)
+        => Input.Select(line =>
         {
-        List<int> numbers = new List<int>();
-        Input.ForEach(line =>
-        {
-            List<char> chars = line.ToList();
-            numbers.Add(Convert.ToInt32($"{chars.First(c => Char.IsDigit(c))}{chars.Last(c => Char.IsDigit(c))}"));
-        });
+            int first = numbers.Select(num => (index: line.IndexOf(num.Key), val: num.Value))
+            .Where(num => num.index >= 0)
+            .MinBy(num => num.index)
+            .val;
 
-        return numbers.Sum();
-    }
-
-    private static int Part2()
-    {
-        string[] validStrNums = { "one", "two", "three", "four", "five", "six", "seven", "eight", "nine", "1", "2", "3", "4", "5", "6", "7", "8", "9" };
-
-        List<int> numbers = new List<int>();
-        Input.ForEach(line =>
-        {
-            int min = line.Length;
-            int max = -1;
-            foreach (var str in validStrNums)
-            {
-                if (!line.Contains(str)) continue;
-
-                int firstIndex = line.IndexOf(str);
-                if (firstIndex < min)
-                {
-                    min = firstIndex;
-                    FirstNum = ParseInt(str);
-                }
-
-                int lastIndex = line.LastIndexOf(str);
-                if (lastIndex > max)
-                {
-                    max = lastIndex;
-                    LastNum = ParseInt(str);
-                }
-            }
-
-            numbers.Add(Convert.ToInt32($"{FirstNum}{LastNum}"));
-        });
-
-        return numbers.Sum();
-    }
-
-    private static int ParseInt(string str)
-    {
-        return (str) switch
-        {
-            "one" => 1,
-            "two" => 2,
-            "three" => 3,
-            "four" => 4,
-            "five" => 5,
-            "six" => 6,
-            "seven" => 7,
-            "eight" => 8,
-            "nine" => 9,
-            _ => Convert.ToInt32(str),
-        };
-    }
+            int last = numbers.Select(num => (index: line.LastIndexOf(num.Key), val: num.Value))
+            .Where(num => num.index >= 0)
+            .MaxBy(num => num.index)
+            .val;
+
+            return first * 10 + last;
+        }).Sum();
 }