Add a new test case and correct the code accordingly

diff --git a/AdventOfCode2017/Day13.fs b/AdventOfCode2017/Day13.fs
index c4b8bf0..b452c04 100644 (file)
--- a/AdventOfCode2017/Day13.fs
+++ b/AdventOfCode2017/Day13.fs
@@ -9,7 +9,7 @@ let parseInput (lines : string[]) =
     )
 
 let severity (input : (int * int)[]) =
-    let inline sum delay =
-        input |> Array.sumBy (fun (d, r) -> if (d + delay) % (2 * r - 2) = 0 then (d + delay) * r else 0)
+    let inline sumBy (f : int -> int -> int) delay =
+        input |> Array.sumBy (fun (d, r) -> if (d + delay) % (2 * r - 2) = 0 then f d r else 0)
 
-    sum 0, Seq.initInfinite (fun i -> i, sum i) |> Seq.pick (fun (i, s) -> if s = 0 then Some i else None)
\ No newline at end of file
+    sumBy (*) 0, Seq.initInfinite (fun i -> i, sumBy (+) i) |> Seq.pick (fun (i, s) -> if s = 0 then Some i else None)
\ No newline at end of file

diff --git a/Tests/Day13 tests.fs b/Tests/Day13 tests.fs
index 5d3437e..3848eec 100644 (file)
--- a/Tests/Day13 tests.fs
+++ b/Tests/Day13 tests.fs
@@ -19,7 +19,6 @@ type ``Day13 tests`` (output : ITestOutputHelper) =
             |]
         Day13.severity (Day13.parseInput input) |> fst =! 24
 
-
     [<Fact>]
     let ``(Part2) From web page`` () =
         let input =
@@ -29,4 +28,13 @@ type ``Day13 tests`` (output : ITestOutputHelper) =
                 "4: 4"
                 "6: 4"
             |]
-        Day13.severity (Day13.parseInput input) |> snd =! 10
\ No newline at end of file
+        Day13.severity (Day13.parseInput input) |> snd =! 10
+
+
+    [<Fact>]
+    let ``(Part2) one depth`` () =
+        let input =
+            [|
+                "0: 3"
+            |]
+        Day13.severity (Day13.parseInput input) |> snd =! 1
\ No newline at end of file