day(01): add solution

Signed-off-by: Matej Focko <mfocko@redhat.com>

src/Day01.kt

@@ -1,17 +1,18 @@
 fun main() {
-    fun part1(input: List<String>): Int {
-        return input.size
+    fun part1(input: List<Int>): Int {
+        return input.windowed(2).count { it[0] < it[1] }
     }
 
-    fun part2(input: List<String>): Int {
-        return input.size
+    fun part2(input: List<Int>): Int {
+        return part1(input.windowed(3).map { it.sum() }.toList())
     }
 
-    // test if implementation meets criteria from the description, like:
-    val testInput = readInput("Day01_test")
-    check(part1(testInput) == 1)
+    val testInput = readInputAsInts("Day01_test")
+    val input = readInputAsInts("Day01")
 
-    val input = readInput("Day01")
+    check(part1(testInput) == 7)
     println(part1(input))
+
+    check(part2(testInput) == 5)
     println(part2(input))
 }

src/Day01_test.txt

@@ -0,0 +1,10 @@
+199
+200
+208
+210
+200
+207
+240
+269
+260
+263

src/Utils.kt

@@ -7,6 +7,8 @@ import java.security.MessageDigest
  */
 fun readInput(name: String) = File("src", "$name.txt").readLines()
 
+fun readInputAsInts(name: String) = readInput(name).map { it.toInt() }
+
 /**
  * Converts string to md5 hash.
  */