Day07 + optimizations

days/src/main/kotlin/Day06.kt

@@ -11,18 +11,16 @@ class Day06(@Text val input: Input<String>) {
 
     private val groups = input.value.split("\n\n")
 
-    fun part1(): Int = groups.map { it.replace("\\s+".toRegex(), "") }
-        .map { it.toCharArray().toSet() }
-        .map { it.size }.sum()
+    fun part1() = groups.sumBy { it.replace("\n", "").toCharArray().toSet().size }
 
-    fun part2(): Int = groups.map {
-        val group = it.split("\n").map { it.trim() }
+    fun part2() = groups.sumBy {
+        val group = it.split("\n")
         val bag = CharBags.mutable.empty()
+
         group.forEach { chars: String -> chars.forEach { bag.add(it) } }
-        bag.selectByOccurrences { group.size == it }
-            .selectUnique()
-            .size()
-    }.sum()
+
+        bag.selectByOccurrences { group.size == it }.toSet().size()
+    }
 
 }