Solved day 18 part 1

Author: Gentleman1983

README.md

@@ -36,7 +36,7 @@ To run all solutions, simply run `./gradlew run`. If you want to run the solutio
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build.gradle

@@ -4,7 +4,7 @@ plugins {
 
 // project meta data
 group 'de.havox_design.aoc2015'
-version '0.17.1'
+version '0.17.2'
 
 // Switch to gradle "all" distribution.
 wrapper {

day18/build.gradle

@@ -1,2 +1,52 @@
+import org.gradle.api.tasks.testing.logging.TestExceptionFormat
+
+plugins {
+    id 'application'
+    id 'org.jetbrains.kotlin.jvm' version '1.9.21'
+}
+
 dependencies {
+    implementation 'org.jetbrains.kotlin:kotlin-reflect'
+    implementation 'org.jetbrains.kotlin:kotlin-stdlib-jdk8'
+
+    testImplementation 'org.junit.jupiter:junit-jupiter:5.10.1'
+    testImplementation 'org.jetbrains.kotlin:kotlin-test-junit'
+    testRuntimeOnly 'org.junit.platform:junit-platform-launcher'
+}
+
+tasks.withType(Test).configureEach {
+    useJUnitPlatform()
+
+    testLogging {
+        exceptionFormat = TestExceptionFormat.FULL
+    }
+
+    reports {
+        junitXml.required = true
+        html.required = true
+    }
+
+    jacocoTestReport.dependsOn(it)
+}
+
+jacocoTestReport {
+    reports {
+        html.required.set(true)
+        xml.required.set(true)
+        xml.outputLocation.set(file("${project.layout.buildDirectory}/jacoco/jacoco.xml"))
+    }
+
+    rootProject.tasks.sonar.dependsOn(it)
+}
+
+jar {
+    manifest {
+        attributes 'Implementation-Title': project.name
+        attributes 'Implementation-Version': project.version
+        attributes 'Main-Class': 'de.havox_design.aoc2015.day16.MainClass'
+    }
+}
+
+application {
+    mainClass = 'de.havox_design.aoc2015.day16.MainClass'
 }

day18/src/main/java/de/havox_design/aoc2015/day18/MainClass.java

@@ -0,0 +1,60 @@
+package de.havox_design.aoc2015.day18
+
+typealias Point = Pair<Int, Int>
+
+class BooleanGrid(val size: Int) : Grid {
+    private val lights = mutableSetOf<Point>()
+
+    override fun turnOn(x: Int, y: Int) {
+        lights += Point(x, y)
+    }
+
+    override fun turnOff(x: Int, y: Int) {
+        lights -= Point(x, y)
+    }
+
+    override fun toggle(x: Int, y: Int) =
+        Point(x, y).let { if (it in lights) lights -= it else lights += it }
+
+    override fun lights() = lights.size
+
+    fun on(x: Int, y: Int) = Point(x, y) in lights
+
+    fun next(): BooleanGrid {
+        val new = BooleanGrid(size)
+        for (x in 0 until size) for (y in 0 until size)
+            if (on(x, y))
+                when (neighbors(x, y)) {
+                    2, 3 -> new.turnOn(x, y)
+                }
+            else
+                when (neighbors(x, y)) {
+                    3 -> new.turnOn(x, y)
+                }
+        return new
+    }
+
+    fun neighbors(x: Int, y: Int): Int {
+        var on = if (on(x, y)) -1 else 0
+        for (dy in -1..1) for (dx in -1..1) {
+            if (on(x + dx, y + dy)) on++
+        }
+        return on
+    }
+
+    fun turnCornersOn(): BooleanGrid {
+        turnOn(0, 0)
+        turnOn(size - 1, 0)
+        turnOn(0, size - 1)
+        turnOn(size - 1, size - 1)
+        return this
+    }
+
+    companion object {
+        fun from(lines: Collection<String>): BooleanGrid {
+            val grid = BooleanGrid(lines.size)
+            lines.forEachIndexed { y, row -> row.forEachIndexed { x, c -> if (c == '#') grid.turnOn(x, y) } }
+            return grid
+        }
+    }
+}

day18/src/main/kotlin/de/havox_design/aoc2015/day18/BooleanGrid.kt

@@ -0,0 +1,19 @@
+package de.havox_design.aoc2015.day18
+
+class GIFMatrix(private var filename: String) {
+    private val data = readData()
+
+    fun processPart1(steps: Int=100): Int =
+        (1..steps)
+            .fold(data) { current, _ -> current.next() }
+            .lights()
+
+    fun processPart2(steps: Int=100): Int =
+        0
+
+    private fun readData(): BooleanGrid =
+        BooleanGrid.from(getResourceAsText(filename))
+
+    private fun getResourceAsText(path: String): List<String> =
+        this.javaClass.classLoader.getResourceAsStream(path)!!.bufferedReader().readLines()
+}

day18/src/main/kotlin/de/havox_design/aoc2015/day18/GIFMatrix.kt

@@ -0,0 +1,8 @@
+package de.havox_design.aoc2015.day18
+
+interface Grid {
+    fun turnOn(x: Int, y: Int)
+    fun turnOff(x: Int, y: Int)
+    fun toggle(x: Int, y: Int)
+    fun lights(): Int
+}

day18/src/main/kotlin/de/havox_design/aoc2015/day18/Grid.kt

@@ -0,0 +1,11 @@
+package de.havox_design.aoc2015.day18
+
+class MainClass {
+    companion object {
+        @JvmStatic
+        fun main(args: Array<String>) {
+            println("Solution 1: ${GIFMatrix("day18.txt").processPart1()}")
+            println("Solution 2: ${GIFMatrix("day18.txt").processPart2()}")
+        }
+    }
+}

day18/src/main/kotlin/de/havox_design/aoc2015/day18/MainClass.kt

@@ -0,0 +1,32 @@
+package de.havox_design.aoc2015.day18
+
+import org.junit.jupiter.api.Assertions
+import org.junit.jupiter.api.Test
+import org.junit.jupiter.params.ParameterizedTest
+import org.junit.jupiter.params.provider.Arguments
+import org.junit.jupiter.params.provider.MethodSource
+import java.util.stream.Stream
+
+class Day18Test {
+    @Test
+    fun testMainClass() =
+        MainClass.Companion.main(arrayOf())
+
+    @ParameterizedTest
+    @MethodSource("getDataForTestProcessPart1")
+    fun testProcessPart1(filename: String, expectedResult: Int, steps: Int) =
+        GIFMatrix(filename).processPart1(steps).shouldBe(expectedResult)
+
+    companion object {
+        @JvmStatic
+        private fun getDataForTestProcessPart1(): Stream<Arguments> =
+            Stream.of(
+                Arguments.of("part1sample.txt", 11, 1),
+                Arguments.of("part1sample.txt", 8, 2),
+                Arguments.of("part1sample.txt", 4, 3),
+                Arguments.of("part1sample.txt", 4, 4)
+            )
+    }
+}
+
+private fun Int.shouldBe(expectation: Int) = Assertions.assertEquals(expectation, this)