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diff --git a/‎src/main/kotlin/advent2021/Day02.kt
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+package advent2021
+
+import Resources
+import advent2021.Day02.DIRECTIVE.DOWN
+import advent2021.Day02.DIRECTIVE.FORWARD
+import advent2021.Day02.DIRECTIVE.UP
+
+class Day02(input: List<String>) {
+
+    private val commands = input.map { Command.of(it) }
+
+    private enum class DIRECTIVE { FORWARD, UP, DOWN }
+
+    private class Command(val directive: DIRECTIVE, val amount: Int) {
+        companion object {
+            fun of(input: String) = input.split(" ").let {
+                Command(
+                    directive = DIRECTIVE.valueOf(it.first().uppercase()),
+                    amount = it.last().toInt()
+                )
+            }
+        }
+    }
+
+    private data class Submarine(
+        val depth: Int = 0,
+        val position: Int = 0,
+        val aim: Int = 0
+    ) {
+        fun answer() = depth * position
+
+        fun movePart1(command: Command): Submarine =
+            when (command.directive) {
+                FORWARD -> copy(position = position + command.amount)
+                DOWN -> copy(depth = depth + command.amount)
+                UP -> copy(depth = depth - command.amount)
+            }
+
+        fun movePart2(command: Command) =
+            when (command.directive) {
+                FORWARD -> copy(
+                    position = position + command.amount,
+                    depth = depth + (aim * command.amount)
+                )
+                DOWN -> copy(aim = aim + command.amount)
+                UP -> copy(aim = aim - command.amount)
+            }
+    }
+
+    fun solvePart1(): Int =
+        commands.fold(Submarine()) { submarine, command -> submarine.movePart1(command) }.answer()
+
+    fun solvePart2(): Int =
+        commands.fold(Submarine()) { submarine, command -> submarine.movePart2(command) }.answer()
+}
+
+fun main() {
+    val input = Resources.resourceAsListOfString("advent2021/day02.txt")
+    val day = Day02(input = input)
+    println("Part 1: ${day.solvePart1()}")
+    println("Part 2: ${day.solvePart2()}")
+}