D18P1

src/main/kotlin/y2024/day18/Day18.kt

@@ -0,0 +1,45 @@
+package y2024.day18
+
+import utils.Point
+import utils.getInputFile
+import utils.shortestPath
+
+fun main() {
+    println("Part one: " + Day18.solvePartOne())
+    println("Part two: " + Day18.solvePartTwo())
+}
+
+object Day18 {
+
+    private val example = false
+    private val p1GridSize = if (example) 6 else 70
+    private val p1Bytes = if (example) 12 else 1024
+
+    private fun parseInput(bytes: Int) = getInputFile(this::class.java.packageName, example = example)
+        .readLines()
+        .take(bytes)
+        .associate {
+            val (x, y) = it.split(",").map(String::toInt)
+            Point(x, y) to '#'
+        }
+
+
+    fun solvePartOne(): Int {
+        val grid = parseInput(p1Bytes)
+
+//        grid.printGrid()
+
+        return grid.shortestPath(
+            start = Point(0, 0),
+            target = Point(p1GridSize, p1GridSize),
+        ) { _, new, _ ->
+            if (new in grid) -1 else 1
+        }.also {
+//            println(it.first)
+        }.second
+    }
+
+    fun solvePartTwo(): Long {
+        return 0
+    }
+}

src/main/kotlin/y2024/day18/example.txt

@@ -0,0 +1,25 @@
+5,4
+4,2
+4,5
+3,0
+2,1
+6,3
+2,4
+1,5
+0,6
+3,3
+2,6
+5,1
+1,2
+5,5
+2,5
+6,5
+1,4
+0,4
+6,4
+1,1
+6,1
+1,0
+0,5
+1,6
+2,0

src/test/kotlin/y2024/day18/Day18Test.kt

@@ -0,0 +1,16 @@
+package y2024.day18
+
+import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Test
+
+internal class Day18Test {
+    @Test
+    fun solvePartOne() {
+        assertEquals(334, Day18.solvePartOne())
+    }
+
+    @Test
+    fun solvePartTwo() {
+        assertEquals(0, Day18.solvePartTwo())
+    }
+}