Simplification

diff --git a/AdventOfCode2017.sln b/AdventOfCode2017.sln
index a1e2b36..78a0214 100644 (file)
--- a/AdventOfCode2017.sln
+++ b/AdventOfCode2017.sln
@@ -8,6 +8,7 @@ EndProject
 Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Solution Items", "Solution Items", "{FC90868D-FFDD-468C-9F0C-3A27EC657C0E}"
        ProjectSection(SolutionItems) = preProject
                .gitignore = .gitignore
+               LICENSE = LICENSE
        EndProjectSection
 EndProject
 Global

diff --git a/AdventOfCode2017/Day1.fs b/AdventOfCode2017/Day1.fs
index 1dfea78..6b2ad1a 100644 (file)
--- a/AdventOfCode2017/Day1.fs
+++ b/AdventOfCode2017/Day1.fs
@@ -2,11 +2,10 @@
 
 let readDigit d = int d - int '0'
 
-let solveCaptchaPart1 (captcha : string) =
-    let numbers = captcha.ToCharArray () |> List.ofArray |> List.map readDigit
-    (List.last numbers :: numbers) |> List.pairwise |> List.map (fun (a, b) -> if a = b then a else 0) |> List.sum
+let solveCaptcha (shift : int) (captcha : string) =
+    let ns = captcha.ToCharArray () |> Array.map readDigit
+    let l = ns.Length
+    [ for i in 0 .. l - 1 -> if ns.[i] = ns.[(i + shift) % l] then ns.[i] else 0 ] |> List.sum
 
-let solveCaptchaPart2 (captcha : string) =
-    let numbers = captcha.ToCharArray () |> Array.map readDigit
-    let l = numbers.Length
-    [ for i in 0 .. l - 1 -> if numbers.[i] = numbers.[(i + l / 2) % l] then numbers.[i] else 0 ] |> List.sum
+let solveCaptcha1 = solveCaptcha 1
+let solveCaptcha2 captcha = solveCaptcha (String.length captcha / 2) captcha

diff --git a/AdventOfCode2017/Program.fs b/AdventOfCode2017/Program.fs
index 5717135..1890a1d 100644 (file)
--- a/AdventOfCode2017/Program.fs
+++ b/AdventOfCode2017/Program.fs
@@ -2,7 +2,7 @@
 
 let day1 () =
     let captcha = "9513446799636685297929646689682997114316733445451534532351778534251427172168183621874641711534917291674333857423799375512628489423332297538215855176592633692631974822259161766238385922277893623911332569448978771948316155868781496698895492971356383996932885518732997624253678694279666572149831616312497994856288871586777793459926952491318336997159553714584541897294117487641872629796825583725975692264125865827534677223541484795877371955124463989228886498682421539667224963783616245646832154384756663251487668681425754536722827563651327524674183443696227523828832466473538347472991998913211857749878157579176457395375632995576569388455888156465451723693767887681392547189273391948632726499868313747261828186732986628365773728583387184112323696592536446536231376615949825166773536471531487969852535699774113163667286537193767515119362865141925612849443983484245268194842563154567638354645735331855896155142741664246715666899824364722914296492444672653852387389477634257768229772399416521198625393426443499223611843766134883441223328256883497423324753229392393974622181429913535973327323952241674979677481518733692544535323219895684629719868384266425386835539719237716339198485163916562434854579365958111931354576991558771236977242668756782139961638347251644828724786827751748399123668854393894787851872256667336215726674348886747128237416273154988619267824361227888751562445622387695218161341884756795223464751862965655559143779425283154533252573949165492138175581615176611845489857169132936848668646319955661492488428427435269169173654812114842568381636982389224236455633316898178163297452453296667661849622174541778669494388167451186352488555379581934999276412919598411422973399319799937518713422398874326665375216437246445791623283898584648278989674418242112957668397484671119761553847275799873495363759266296477844157237423239163559391553961176475377151369399646747881452252547741718734949967752564774161341784833521492494243662658471121369649641815562327698395293573991648351369767162642763475561544795982183714447737149239846151871434656618825566387329765118727515699213962477996399781652131918996434125559698427945714572488376342126989157872118279163127742349"
-    sprintf "part1 = %A, part2 = %A" (Day1.solveCaptchaPart1 captcha) (Day1.solveCaptchaPart2 captcha)
+    sprintf "part1 = %A, part2 = %A" (Day1.solveCaptcha1 captcha) (Day1.solveCaptcha2 captcha)
 
 let printDay (n : int) (f : unit -> string) =
     printfn "Result of day %i: %s" n (f ())