day 9 puzzle 1

tests/day9/Puzzle1Test.scala

@@ -0,0 +1,9 @@
+package day9
+
+import org.scalatest.funsuite.AnyFunSuite
+
+class Puzzle1Test extends AnyFunSuite {
+  test("Puzzle1.solve") {
+    assert(Puzzle1.solve("tests_res/day9/input1.txt") == 114)
+  }
+}