complete day 5

05-a.kts

@@ -0,0 +1,39 @@
+import java.util.Scanner
+
+val scanner = Scanner(System.`in`)
+
+val rules = HashMap<Int, MutableSet<Int>>()
+
+while (scanner.hasNextLine()) {
+    val line = scanner.nextLine()
+    if (line == "") {
+        break;
+    }
+
+    val (before, after) = line.split("|").map(String::toInt)
+    if (!rules.contains(before)) {
+        rules[before] = HashSet<Int>()
+    }
+    rules[before]!!.add(after)
+}
+
+var sum = 0
+while (scanner.hasNextLine()) {
+    val line = scanner.nextLine()
+    val pages = line.split(",").map(String::toInt)
+
+    val result = pages.fold(Pair(HashSet<Int>(), true)) { (appeared, isSafe), page ->
+        val shouldBeAfter = rules[page]?.toSet() ?: emptySet()
+        val violateRule = appeared.intersect(shouldBeAfter)
+        val stillSafe = isSafe && violateRule.isEmpty()
+
+        appeared.add(page)
+        Pair(appeared, stillSafe)
+    }
+
+    if (result.second) {
+        val pagesArray = pages.toIntArray()
+        sum += pagesArray[pagesArray.size / 2]
+    }
+}
+println(sum)

05-b.kts

@@ -0,0 +1,31 @@
+import java.util.Scanner
+
+val scanner = Scanner(System.`in`)
+
+val rules = HashMap<Int, MutableSet<Int>>()
+
+while (scanner.hasNextLine()) {
+    val line = scanner.nextLine()
+    if (line == "") {
+        break;
+    }
+
+    val (before, after) = line.split("|").map(String::toInt)
+    if (!rules.contains(before)) {
+        rules[before] = HashSet<Int>()
+    }
+    rules[before]!!.add(after)
+}
+
+var sum = 0
+while (scanner.hasNextLine()) {
+    val line = scanner.nextLine()
+    val pages = line.split(",").map(String::toInt)
+    val fixed = pages.sortedWith { l, r -> if (l == r) 0 else if (rules[l]?.contains(r) == true) -1 else 1 }
+
+    if ("$pages" != "$fixed") {
+        val fixedArray = fixed.toIntArray()
+        sum += fixedArray[fixedArray.size / 2]
+    }
+}
+println(sum)