diff --git a/config.json b/config.json index 96dd333f..cb0293b0 100644 --- a/config.json +++ b/config.json @@ -1251,6 +1251,20 @@ ], "difficulty": 5 }, + { + "slug": "secret-handshake", + "name": "Secret Handshake", + "uuid": "6c7a96ec-0bfb-4284-bd9f-2aa6989c3bb5", + "practices": [], + "prerequisites": [ + "custom-types", + "pattern-matching", + "maybe", + "lists", + "booleans" + ], + "difficulty": 4 + }, { "slug": "sieve", "name": "Sieve", diff --git a/exercises/practice/secret-handshake/.docs/instructions.md b/exercises/practice/secret-handshake/.docs/instructions.md new file mode 100644 index 00000000..d2120b9b --- /dev/null +++ b/exercises/practice/secret-handshake/.docs/instructions.md @@ -0,0 +1,48 @@ +# Instructions + +Your task is to convert a number between 1 and 31 to a sequence of actions in the secret handshake. + +The sequence of actions is chosen by looking at the rightmost five digits of the number once it's been converted to binary. +Start at the right-most digit and move left. + +The actions for each number place are: + +```plaintext +00001 = wink +00010 = double blink +00100 = close your eyes +01000 = jump +10000 = Reverse the order of the operations in the secret handshake. +``` + +Let's use the number `9` as an example: + +- 9 in binary is `1001`. +- The digit that is farthest to the right is 1, so the first action is `wink`. +- Going left, the next digit is 0, so there is no double-blink. +- Going left again, the next digit is 0, so you leave your eyes open. +- Going left again, the next digit is 1, so you jump. + +That was the last digit, so the final code is: + +```plaintext +wink, jump +``` + +Given the number 26, which is `11010` in binary, we get the following actions: + +- double blink +- jump +- reverse actions + +The secret handshake for 26 is therefore: + +```plaintext +jump, double blink +``` + +~~~~exercism/note +If you aren't sure what binary is or how it works, check out [this binary tutorial][intro-to-binary]. + +[intro-to-binary]: https://medium.com/basecs/bits-bytes-building-with-binary-13cb4289aafa +~~~~ diff --git a/exercises/practice/secret-handshake/.docs/introduction.md b/exercises/practice/secret-handshake/.docs/introduction.md new file mode 100644 index 00000000..176b92e8 --- /dev/null +++ b/exercises/practice/secret-handshake/.docs/introduction.md @@ -0,0 +1,7 @@ +# Introduction + +You are starting a secret coding club with some friends and friends-of-friends. +Not everyone knows each other, so you and your friends have decided to create a secret handshake that you can use to recognize that someone is a member. +You don't want anyone who isn't in the know to be able to crack the code. + +You've designed the code so that one person says a number between 1 and 31, and the other person turns it into a series of actions. diff --git a/exercises/practice/secret-handshake/.meta/config.json b/exercises/practice/secret-handshake/.meta/config.json new file mode 100644 index 00000000..fc2dbf0f --- /dev/null +++ b/exercises/practice/secret-handshake/.meta/config.json @@ -0,0 +1,19 @@ +{ + "authors": [ + "jiegillet" + ], + "files": { + "solution": [ + "src/SecretHandshake.elm" + ], + "test": [ + "tests/Tests.elm" + ], + "example": [ + ".meta/src/SecretHandshake.example.elm" + ] + }, + "blurb": "Given a decimal number, convert it to the appropriate sequence of events for a secret handshake.", + "source": "Bert, in Mary Poppins", + "source_url": "https://www.imdb.com/title/tt0058331/quotes/?item=qt0437047" +} diff --git a/exercises/practice/secret-handshake/.meta/src/SecretHandshake.example.elm b/exercises/practice/secret-handshake/.meta/src/SecretHandshake.example.elm new file mode 100644 index 00000000..0b3c19e7 --- /dev/null +++ b/exercises/practice/secret-handshake/.meta/src/SecretHandshake.example.elm @@ -0,0 +1,55 @@ +module SecretHandshake exposing (Command(..), commands) + +import Bitwise + + +type Command + = Wink + | DoubleBlink + | CloseYourEyes + | Jump + | Reverse + + +commandToCode : Command -> Int +commandToCode command = + case command of + Wink -> + 1 + + DoubleBlink -> + 2 + + CloseYourEyes -> + 4 + + Jump -> + 8 + + Reverse -> + 16 + + +commandApplies : Int -> Command -> Bool +commandApplies number command = + Bitwise.and number (commandToCode command) > 0 + + +commands : Int -> List Command +commands number = + let + maybeAction command = + if commandApplies number command then + Just command + + else + Nothing + + actions = + List.filterMap maybeAction [ Wink, DoubleBlink, CloseYourEyes, Jump ] + in + if commandApplies number Reverse then + List.reverse actions + + else + actions diff --git a/exercises/practice/secret-handshake/.meta/tests.toml b/exercises/practice/secret-handshake/.meta/tests.toml new file mode 100644 index 00000000..f318e528 --- /dev/null +++ b/exercises/practice/secret-handshake/.meta/tests.toml @@ -0,0 +1,43 @@ +# This is an auto-generated file. +# +# Regenerating this file via `configlet sync` will: +# - Recreate every `description` key/value pair +# - Recreate every `reimplements` key/value pair, where they exist in problem-specifications +# - Remove any `include = true` key/value pair (an omitted `include` key implies inclusion) +# - Preserve any other key/value pair +# +# As user-added comments (using the # character) will be removed when this file +# is regenerated, comments can be added via a `comment` key. + +[b8496fbd-6778-468c-8054-648d03c4bb23] +description = "wink for 1" + +[83ec6c58-81a9-4fd1-bfaf-0160514fc0e3] +description = "double blink for 10" + +[0e20e466-3519-4134-8082-5639d85fef71] +description = "close your eyes for 100" + +[b339ddbb-88b7-4b7d-9b19-4134030d9ac0] +description = "jump for 1000" + +[40499fb4-e60c-43d7-8b98-0de3ca44e0eb] +description = "combine two actions" + +[9730cdd5-ef27-494b-afd3-5c91ad6c3d9d] +description = "reverse two actions" + +[0b828205-51ca-45cd-90d5-f2506013f25f] +description = "reversing one action gives the same action" + +[9949e2ac-6c9c-4330-b685-2089ab28b05f] +description = "reversing no actions still gives no actions" + +[23fdca98-676b-4848-970d-cfed7be39f81] +description = "all possible actions" + +[ae8fe006-d910-4d6f-be00-54b7c3799e79] +description = "reverse all possible actions" + +[3d36da37-b31f-4cdb-a396-d93a2ee1c4a5] +description = "do nothing for zero" diff --git a/exercises/practice/secret-handshake/elm.json b/exercises/practice/secret-handshake/elm.json new file mode 100644 index 00000000..22c9e137 --- /dev/null +++ b/exercises/practice/secret-handshake/elm.json @@ -0,0 +1,29 @@ +{ + "type": "application", + "source-directories": [ + "src" + ], + "elm-version": "0.19.1", + "dependencies": { + "direct": { + "elm/core": "1.0.5", + "elm/json": "1.1.3", + "elm/parser": "1.1.0", + "elm/random": "1.0.0", + "elm/regex": "1.0.0", + "elm/time": "1.0.0" + }, + "indirect": {} + }, + "test-dependencies": { + "direct": { + "elm-explorations/test": "2.1.0", + "rtfeldman/elm-iso8601-date-strings": "1.1.4" + }, + "indirect": { + "elm/bytes": "1.0.8", + "elm/html": "1.0.0", + "elm/virtual-dom": "1.0.3" + } + } +} diff --git a/exercises/practice/secret-handshake/src/SecretHandshake.elm b/exercises/practice/secret-handshake/src/SecretHandshake.elm new file mode 100644 index 00000000..eee47c8d --- /dev/null +++ b/exercises/practice/secret-handshake/src/SecretHandshake.elm @@ -0,0 +1,13 @@ +module SecretHandshake exposing (Command(..), commands) + + +type Command + = Wink + | DoubleBlink + | CloseYourEyes + | Jump + + +commands : Int -> List Command +commands number = + Debug.todo "Please implement commands" diff --git a/exercises/practice/secret-handshake/tests/Tests.elm b/exercises/practice/secret-handshake/tests/Tests.elm new file mode 100644 index 00000000..67bd7e6f --- /dev/null +++ b/exercises/practice/secret-handshake/tests/Tests.elm @@ -0,0 +1,66 @@ +module Tests exposing (tests) + +import Expect +import SecretHandshake exposing (Command(..)) +import Test exposing (Test, describe, skip, test) + + +tests : Test +tests = + describe "SecretHandshake" + [ -- skip <| + test "wink for 1" <| + \() -> + SecretHandshake.commands 1 + |> Expect.equal [ Wink ] + , skip <| + test "double blink for 10" <| + \() -> + SecretHandshake.commands 2 + |> Expect.equal [ DoubleBlink ] + , skip <| + test "close your eyes for 100" <| + \() -> + SecretHandshake.commands 4 + |> Expect.equal [ CloseYourEyes ] + , skip <| + test "jump for 1000" <| + \() -> + SecretHandshake.commands 8 + |> Expect.equal [ Jump ] + , skip <| + test "combine two actions" <| + \() -> + SecretHandshake.commands 3 + |> Expect.equal [ Wink, DoubleBlink ] + , skip <| + test "reverse two actions" <| + \() -> + SecretHandshake.commands 19 + |> Expect.equal [ DoubleBlink, Wink ] + , skip <| + test "reversing one action gives the same action" <| + \() -> + SecretHandshake.commands 24 + |> Expect.equal [ Jump ] + , skip <| + test "reversing no actions still gives no actions" <| + \() -> + SecretHandshake.commands 16 + |> Expect.equal [] + , skip <| + test "all possible actions" <| + \() -> + SecretHandshake.commands 15 + |> Expect.equal [ Wink, DoubleBlink, CloseYourEyes, Jump ] + , skip <| + test "reverse all possible actions" <| + \() -> + SecretHandshake.commands 31 + |> Expect.equal [ Jump, CloseYourEyes, DoubleBlink, Wink ] + , skip <| + test "do nothing for zero" <| + \() -> + SecretHandshake.commands 0 + |> Expect.equal [] + ]