day 3 part 2

src/main/scala/Day03.scala

@@ -2,9 +2,8 @@ import scala.util.Success
 import scala.util.Failure
 import scala.util.boundary
 
-
 object Day03 extends Solution:
-    override def part_01() = 
+    override def part_01() =
         val file = read_input("03") match
             case Success(f) => f
             case Failure(ex) =>
@@ -18,18 +17,67 @@ object Day03 extends Solution:
             val second_segment = line.slice(char_count / 2, char_count)
 
             val set = first_segment.toList.toSet
-            val res_char = second_segment.toCharArray().find((char) => set.contains(char)) match
+            val res_char = second_segment
+                .toCharArray()
+                .find((char) => set.contains(char)) match
                 case Some(c) => c
                 case None =>
                     return "Error: Input didn't have a repeating character"
 
             sum += char_to_value(res_char)
 
-
         s"part 1: $sum"
 
-    override def part_02() = ""
+    override def part_02() =
+        val file = read_input("03") match
+            case Success(f) => f
+            case Failure(ex) =>
+                return "Error opening file: " + ex.getMessage()
 
+        var (line0, line1, line2) = ("", "", "")
+        var line_count = 0
+        var sum = 0
+
+        for line <- file.getLines() do
+            line_count match
+                case 0 =>
+                    line0 = line
+                    line_count += 1
+                case 1 =>
+                    line1 = line
+                    line_count += 1
+                case 2 =>
+                    line2 = line
+                    line_count = 0
+
+                    // Process the 3 lines
+                    var map = collection.mutable.Map[Char, Int]()
+
+                    for
+                        char <- line0
+                        if !map.contains(char)
+                    do map(char) = 1
+
+                    for
+                        char <- line1
+                        if map.contains(char)
+                    do map(char) = 2
+
+                    for
+                        char <- line2
+                        if map.contains(char)
+                        if map(char) == 2
+                    do map(char) = 3
+
+                    val result = map.find((_, count) => count == 3) match
+                        case Some((char, _)) => char
+                        case None =>
+                            println("Repeat not found in group.")
+                            '0'
+
+                    sum += char_to_value(result)
+
+        s"part 2: $sum"
 
     private def char_to_value(c: Char): Int =
         if c >= 'a' && c <= 'z' then c.toInt - 96
@@ -37,4 +85,3 @@ object Day03 extends Solution:
         else
             println(s"fed an invalid character: $c")
             -1
-