Переписывание

Tasks/Test/Test.Tests/QueueTests.fs

@@ -0,0 +1,59 @@
+module Queue.Tests
+
+open NUnit.Framework
+open FsUnit
+open System
+
+[<Test>]
+let testEnqueue_AddElements_SizeShouldBeCorrect () =
+    let queue = new Queue<int> ()
+    queue.Count |> should equal 0
+    for x in { 1 .. 100 } do
+        queue.Enqueue x
+    queue.Count |> should equal 100
+
+[<Test>]
+let testDequeue_AddEndGetElements_ObtainElementsInOrderOfAddition () =
+    let queue = new Queue<int> ()
+    queue.Enqueue -100
+    queue.Enqueue 42
+    queue.Enqueue 0
+    queue.Enqueue Int32.MaxValue
+    queue.Enqueue Int32.MinValue
+    queue.Dequeue () |> should equal -100
+    queue.Dequeue () |> should equal 42
+    queue.Dequeue () |> should equal 0
+    queue.Count |> should equal 2
+    queue.Dequeue () |> should equal Int32.MaxValue
+    queue.Dequeue () |> should equal Int32.MinValue
+    queue.Count |> should equal 0
+
+[<Test>]
+let testDequeue_GetFromEmptyQueue_ThrowException () =
+    let queue = new Queue<string> ()
+    (fun () -> queue.Dequeue () |> ignore) |> should throw typeof<InvalidOperationException>
+    queue.Count |> should equal 0
+
+[<Test>]
+let testDequeue_RemoveAllElementsAndGetFromEmpty_ThrowException () =
+    let queue = new Queue<float> ()
+    queue.Enqueue 10.0
+    queue.Enqueue 12.2
+    queue.Dequeue () |> should equal 10.0
+    queue.Dequeue () |> should equal 12.2
+    (fun () -> queue.Dequeue () |> ignore) |> should throw typeof<InvalidOperationException>
+    queue.Count |> should equal 0
+
+[<Test>]
+let testDequeue_RemoveElementsAndAddNewOnes_ElementsAreAdded () =
+    let queue = new Queue<string> ()
+    queue.Enqueue "trololo"
+    queue.Enqueue ""
+    queue.Dequeue () |> should equal "trololo"
+    queue.Dequeue () |> should equal ""
+    queue.Count |> should equal 0
+    queue.Enqueue "test"
+    queue.Enqueue "a"
+    queue.Count |> should equal 2
+    queue.Dequeue () |> should equal "test"
+    queue.Dequeue () |> should equal "a"

Tasks/Test/Test.Tests/Test.Tests.fsproj

@@ -10,6 +10,7 @@
   <ItemGroup>
     <Compile Include="BinaryTreeTests.fs" />
     <Compile Include="InfiniteSequenceTests.fs" />
+    <Compile Include="QueueTests.fs" />
     <Compile Include="Program.fs" />
   </ItemGroup>
 

Tasks/Test/Test/Queue.fs

@@ -0,0 +1,50 @@
+namespace Queue
+
+open System
+
+/// Class representing an element in a linked list.
+type Node<'a>(value: 'a, next: Node<'a> option) =
+    let mutable value = value
+    let mutable next = next
+
+    /// Get the value of the node.
+    member _.Value: 'a = value
+
+    /// Get the next node of the current one.
+    member _.Next: Node<'a> option = next
+
+    /// Set the next node of the current one.
+    member _.SetNext (node: Node<'a> option) = next <- node
+
+/// Class representing a generic queue.
+type Queue<'a>() =
+    let mutable head: Node<'a> option = None
+    let mutable tail: Node<'a> option = None
+    let mutable count = 0
+
+    /// Get the size of the queue.
+    member _.Count: int = count
+
+    /// Add the given `value` to the queue.
+    member _.Enqueue (value: 'a): unit =
+        let next = Node (value, None)
+        match tail with
+        | Some node ->
+            node.SetNext <| Some next
+            tail <- Some next
+        | None ->
+            head <- Some next
+            tail <- Some next
+        count <- count + 1
+
+    /// Remove the first element from the queue and return its value.
+    member _.Dequeue (): 'a =
+        match head with
+        | Some node ->
+            let res = node.Value
+            head <- node.Next
+            if head.IsNone then tail <- None
+            count <- count - 1
+            res
+        | None ->
+            raise (new InvalidOperationException "Error on dequeue: queue was empty")

Tasks/Test/Test/Test.fsproj

@@ -8,6 +8,7 @@
   <ItemGroup>
     <Compile Include="BinaryTree.fs" />
     <Compile Include="InfiniteSequence.fs" />
+    <Compile Include="Queue.fs" />
   </ItemGroup>
 
 </Project>