[New Exercise]: Bowling (#326)

config.json

@@ -1000,6 +1000,14 @@
         "prerequisites": [],
         "difficulty": 6
       },
+      {
+        "slug": "bowling",
+        "name": "Bowling",
+        "uuid": "f374b4a0-d2a2-40c2-bd41-215b0fd64316",
+        "practices": ["classes"],
+        "prerequisites": [],
+        "difficulty": 6
+      },
       {
         "slug": "book-store",
         "name": "Book Store",

exercises/practice/bowling/.docs/instructions.md

@@ -0,0 +1,56 @@
+# Instructions
+
+Score a bowling game.
+
+Bowling is a game where players roll a heavy ball to knock down pins arranged in a triangle.
+Write code to keep track of the score of a game of bowling.
+
+## Scoring Bowling
+
+The game consists of 10 frames.
+A frame is composed of one or two ball throws with 10 pins standing at frame initialization.
+There are three cases for the tabulation of a frame.
+
+- An open frame is where a score of less than 10 is recorded for the frame.
+  In this case the score for the frame is the number of pins knocked down.
+
+- A spare is where all ten pins are knocked down by the second throw.
+  The total value of a spare is 10 plus the number of pins knocked down in their next throw.
+
+- A strike is where all ten pins are knocked down by the first throw.
+  The total value of a strike is 10 plus the number of pins knocked down in the next two throws.
+  If a strike is immediately followed by a second strike, then the value of the first strike cannot be determined until the ball is thrown one more time.
+
+Here is a three frame example:
+
+|  Frame 1   |  Frame 2   |     Frame 3      |
+| :--------: | :--------: | :--------------: |
+| X (strike) | 5/ (spare) | 9 0 (open frame) |
+
+Frame 1 is (10 + 5 + 5) = 20
+
+Frame 2 is (5 + 5 + 9) = 19
+
+Frame 3 is (9 + 0) = 9
+
+This means the current running total is 48.
+
+The tenth frame in the game is a special case.
+If someone throws a spare or a strike then they get one or two fill balls respectively.
+Fill balls exist to calculate the total of the 10th frame.
+Scoring a strike or spare on the fill ball does not give the player more fill balls.
+The total value of the 10th frame is the total number of pins knocked down.
+
+For a tenth frame of X1/ (strike and a spare), the total value is 20.
+
+For a tenth frame of XXX (three strikes), the total value is 30.
+
+## Requirements
+
+Write code to keep track of the score of a game of bowling.
+It should support two operations:
+
+- `roll(pins : int)` is called each time the player rolls a ball.
+  The argument is the number of pins knocked down.
+- `score() : int` is called only at the very end of the game.
+  It returns the total score for that game.

exercises/practice/bowling/.meta/Bowling.example.ps1

@@ -0,0 +1,127 @@
+<#
+.SYNOPSIS
+    Implement a class to score a bowling game.
+
+.DESCRIPTION
+    For the detailed rules of the game, check instructions.
+
+    Write code to keep track of the score of a game of bowling.
+    It should support two operations:
+
+    - roll(pins): is called each time the player rolls a ball.
+    The argument is an integer represent the number of pins got knocked down (0 - 10)
+
+    - score(): is called only at the very end of the game.
+    It returns an integer represent the total score for that game.
+
+    The class also should handle various cases of errors based on invalid or illegal inputs.
+    You can decide what error message you want to throw.
+    
+.EXAMPLE
+    $rolls = @(10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10)
+    $game = [BowlingGame]::new()
+
+    foreach ($roll in $rolls) {
+        $game.Roll($roll)
+    }
+    $game.Score()
+    Returns: 300
+#>
+Class Frame {
+    [int]   $Number
+    [int[]] $Throws
+    [int]   $Score
+    [Frame] $Next
+
+    Frame([int]$number) {
+        $this.Number = $number
+        $this.Throws = @()
+        $this.Score  = 0
+        $this.Next   = $null
+    }
+
+    [void] Update([int]$pins) {
+        <#
+        .DESCRIPTION
+        Function to update the frame with new pins, and handle error if the pin invalid the frame
+        #>
+        $this.Throws += $pins
+        $this.Score  += $pins
+
+        if ($this.Throws.Count -eq 3) {
+            $sum = $this.Throws[1] + $this.Throws[2]
+            if ($this.Throws[0] -eq 10 -and $this.Throws[1] -lt 10 -and $sum -gt 10) {
+                Throw "Two rolls in bonus spare can't be more than 10 points"
+            }
+        }else {
+            if ($this.Score -gt 10 -and $this.Throws[0] -lt 10) {
+                Throw "Two rolls in a spare can't be more than 10 points"
+            }
+        }
+    }
+
+    #boolean logic to handle frame
+    [bool] IsStrike() {
+        return $this.Score -eq 10 -and $this.Throws.Count -eq 1
+    }
+
+    [bool] IsSpare() {
+        return $this.Score -eq 10 -and $this.Throws.Count -eq 2
+    }
+
+    [bool] IsComplete() {
+        if ($this.Number -eq 10) {
+            return ($this.Score -lt 10 -and $this.Throws.Count -eq 2) -or ($this.Throws.Count -eq 3)
+        }
+        return $this.IsStrike() -or $this.Throws.Count -eq 2
+    }
+}
+
+Class BowlingGame {
+    [Frame] hidden $Head
+    [Frame] hidden $CurrentFrame
+
+    BowlingGame() {
+        $this.CurrentFrame = $null
+        $this.Head = $null
+    }
+
+    [void] Roll([int]$pins) {
+        if ($pins -lt 0 -or $pins -gt 10) {Throw "Invalid number of pin"}
+
+        if ($null -eq $this.Head) {
+            $this.CurrentFrame = [Frame]::new(1)
+            $this.Head = $this.CurrentFrame
+        }
+
+        if ($this.CurrentFrame.IsComplete()) {
+            if ($this.CurrentFrame.Number -eq 10) {Throw "Game's finished. Can't make any more roll"}
+            $this.CurrentFrame.Next = [Frame]::new($this.CurrentFrame.Number + 1)
+            $this.CurrentFrame = $this.CurrentFrame.Next
+        }
+        $this.CurrentFrame.Update($pins)
+    }
+
+    [int] Score() {
+        if ($null -eq $this.Head) {
+            Throw "Can't score game that hasn't started" 
+        }
+
+        if ($this.CurrentFrame.Number -lt 10 -or (-not $this.CurrentFrame.IsComplete())) {
+            Throw "Can't score incomplete game" 
+        }
+
+        $total = 0
+        while ($this.Head) {
+            $total += $this.Head.Score
+            $nextThrows = $this.Head.Next.Throws + $this.Head.Next.Next.Throws
+            if ($this.Head.IsSpare()) {
+                $total += $nextThrows[0]
+            }elseif ($this.Head.IsStrike()) {
+                $total += $nextThrows[0] + $nextThrows[1]
+            }
+            $this.Head = $this.Head.Next
+        }
+        return $total
+    }
+}

exercises/practice/bowling/.meta/config.json

@@ -0,0 +1,19 @@
+{
+  "authors": [
+    "glaxxie"
+  ],
+  "files": {
+    "solution": [
+      "Bowling.ps1"
+    ],
+    "test": [
+      "Bowling.tests.ps1"
+    ],
+    "example": [
+      ".meta/Bowling.example.ps1"
+    ]
+  },
+  "blurb": "Score a bowling game.",
+  "source": "The Bowling Game Kata from UncleBob",
+  "source_url": "https://web.archive.org/web/20221001111000/http://butunclebob.com/ArticleS.UncleBob.TheBowlingGameKata"
+}

exercises/practice/bowling/.meta/tests.toml

@@ -0,0 +1,103 @@
+# 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.
+
+[656ae006-25c2-438c-a549-f338e7ec7441]
+description = "should be able to score a game with all zeros"
+
+[f85dcc56-cd6b-4875-81b3-e50921e3597b]
+description = "should be able to score a game with no strikes or spares"
+
+[d1f56305-3ac2-4fe0-8645-0b37e3073e20]
+description = "a spare followed by zeros is worth ten points"
+
+[0b8c8bb7-764a-4287-801a-f9e9012f8be4]
+description = "points scored in the roll after a spare are counted twice"
+
+[4d54d502-1565-4691-84cd-f29a09c65bea]
+description = "consecutive spares each get a one roll bonus"
+
+[e5c9cf3d-abbe-4b74-ad48-34051b2b08c0]
+description = "a spare in the last frame gets a one roll bonus that is counted once"
+
+[75269642-2b34-4b72-95a4-9be28ab16902]
+description = "a strike earns ten points in a frame with a single roll"
+
+[037f978c-5d01-4e49-bdeb-9e20a2e6f9a6]
+description = "points scored in the two rolls after a strike are counted twice as a bonus"
+
+[1635e82b-14ec-4cd1-bce4-4ea14bd13a49]
+description = "consecutive strikes each get the two roll bonus"
+
+[e483e8b6-cb4b-4959-b310-e3982030d766]
+description = "a strike in the last frame gets a two roll bonus that is counted once"
+
+[9d5c87db-84bc-4e01-8e95-53350c8af1f8]
+description = "rolling a spare with the two roll bonus does not get a bonus roll"
+
+[576faac1-7cff-4029-ad72-c16bcada79b5]
+description = "strikes with the two roll bonus do not get bonus rolls"
+
+[efb426ec-7e15-42e6-9b96-b4fca3ec2359]
+description = "last two strikes followed by only last bonus with non strike points"
+
+[72e24404-b6c6-46af-b188-875514c0377b]
+description = "a strike with the one roll bonus after a spare in the last frame does not get a bonus"
+
+[62ee4c72-8ee8-4250-b794-234f1fec17b1]
+description = "all strikes is a perfect game"
+
+[1245216b-19c6-422c-b34b-6e4012d7459f]
+description = "rolls cannot score negative points"
+
+[5fcbd206-782c-4faa-8f3a-be5c538ba841]
+description = "a roll cannot score more than 10 points"
+
+[fb023c31-d842-422d-ad7e-79ce1db23c21]
+description = "two rolls in a frame cannot score more than 10 points"
+
+[6082d689-d677-4214-80d7-99940189381b]
+description = "bonus roll after a strike in the last frame cannot score more than 10 points"
+
+[e9565fe6-510a-4675-ba6b-733a56767a45]
+description = "two bonus rolls after a strike in the last frame cannot score more than 10 points"
+
+[2f6acf99-448e-4282-8103-0b9c7df99c3d]
+description = "two bonus rolls after a strike in the last frame can score more than 10 points if one is a strike"
+
+[6380495a-8bc4-4cdb-a59f-5f0212dbed01]
+description = "the second bonus rolls after a strike in the last frame cannot be a strike if the first one is not a strike"
+
+[2b2976ea-446c-47a3-9817-42777f09fe7e]
+description = "second bonus roll after a strike in the last frame cannot score more than 10 points"
+
+[29220245-ac8d-463d-bc19-98a94cfada8a]
+description = "an unstarted game cannot be scored"
+
+[4473dc5d-1f86-486f-bf79-426a52ddc955]
+description = "an incomplete game cannot be scored"
+
+[2ccb8980-1b37-4988-b7d1-e5701c317df3]
+description = "cannot roll if game already has ten frames"
+
+[4864f09b-9df3-4b65-9924-c595ed236f1b]
+description = "bonus rolls for a strike in the last frame must be rolled before score can be calculated"
+
+[537f4e37-4b51-4d1c-97e2-986eb37b2ac1]
+description = "both bonus rolls for a strike in the last frame must be rolled before score can be calculated"
+
+[8134e8c1-4201-4197-bf9f-1431afcde4b9]
+description = "bonus roll for a spare in the last frame must be rolled before score can be calculated"
+
+[9d4a9a55-134a-4bad-bae8-3babf84bd570]
+description = "cannot roll after bonus roll for spare"
+
+[d3e02652-a799-4ae3-b53b-68582cc604be]
+description = "cannot roll after bonus rolls for strike"

exercises/practice/bowling/Bowling.ps1

@@ -0,0 +1,42 @@
+<#
+.SYNOPSIS
+    Implement a class to score a bowling game.
+
+.DESCRIPTION
+    For the detailed rules of the game, check instructions.
+
+    Write code to keep track of the score of a game of bowling.
+    It should support two operations:
+
+    - roll(pins): is called each time the player rolls a ball.
+    The argument is an integer represent the number of pins got knocked down (0 - 10)
+
+    - score(): is called only at the very end of the game.
+    It returns an integer represent the total score for that game.
+
+    The class also should handle various cases of errors based on invalid or illegal inputs.
+    You can decide what error message you want to throw.
+
+.EXAMPLE
+    $rolls = @(10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10)
+    $game = [BowlingGame]::new()
+
+    foreach ($roll in $rolls) {
+        $game.Roll($roll)
+    }
+    $game.Score()
+    Returns: 300
+#>
+Class BowlingGame {
+    BowlingGame() {
+        Throw "Please implement this class"
+    }
+
+    Roll($pins) {
+        Throw "Please implement this fucntion"
+    }
+
+    Score() {
+        Throw "Please implement this fucntion"
+    }
+}