First two days

puzzle1.kts

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+import java.io.File
+import java.util.Scanner
+import kotlin.math.abs
+
+val scanner = Scanner(File("puzzle1input.txt"))
+val firstList = mutableListOf<Int>()
+val secondList = mutableListOf<Int>()
+var secondMap = mutableMapOf<Int, Int>()
+while (scanner.hasNextLine()) {
+    val line = scanner.nextLine()
+    val numbers = line.split("   ")
+    val firstNumber = numbers[0].toInt()
+    val secondNumber = numbers[1].toInt()
+    firstList.add(firstNumber)
+    secondList.add(secondNumber)
+    secondMap[secondNumber] = (secondMap[secondNumber] ?: 0) + 1
+}
+firstList.sort()
+secondList.sort()
+var totaldistance = 0
+var similarityscore = 0
+for (i in firstList.indices) {
+    val distance = abs(firstList[i] - secondList[i])
+    totaldistance += distance
+    similarityscore += (secondMap[firstList[i]] ?: 0) * firstList[i]
+}
+println(totaldistance)
+println(similarityscore)

puzzle2.kts

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+import java.io.File
+import java.util.Scanner
+import javax.print.attribute.standard.NumberUpSupported
+import kotlin.math.abs
+
+val scanner = Scanner(File("puzzle2input.txt"))
+var safelines = 0
+var dampenedsafelines = 0
+while (scanner.hasNextLine()) {
+    val line = scanner.nextLine()
+    val numbers = line.split(" ").map { it.toInt() }
+    if (isSafe(numbers)) {
+        safelines++
+    } else if (dampenedSafe(numbers)) {
+        dampenedsafelines++
+    }
+}
+println(safelines)
+println(dampenedsafelines + safelines)
+
+fun isSafe(numbers: List<Int> ): Boolean {
+    var directionality = 0
+    for (i in 1 until numbers.size) {
+        val direction = if (numbers[i] > numbers[i - 1]) 1 else -1
+        if (directionality == 0) {
+            directionality = direction
+        } else if (directionality != direction) {
+            return false
+        }
+        val difference = abs(numbers[i] - numbers[i - 1])
+        if (difference < 1 || difference > 3) {
+            return false
+        }
+    }
+    return true
+}
+
+fun dampenedSafe(numbers: List<Int>): Boolean {
+    // Brute force approach
+    for (i in numbers.indices) {
+        val copy = numbers.toMutableList()
+        copy.removeAt(i)
+        if (isSafe(copy)) {
+            return true
+        }
+    }
+    return false
+}