帕斯卡'；s三角形-VB.NET

我已经创建了一个程序，该程序将显示x行数，并重复该操作：

i、 e

---

现在我想做一个帕斯卡三角形，可能是这样的：

Dim arr As Integer(,) = New Integer(7, 7) {}
 For i As Integer = 0 To 7
    For k As Integer = 7 To i + 1 Step -1
        'print spaces
        Console.Write(" ")
    Next

    For j As Integer = 0 To i - 1
        If j = 0 OrElse i = j Then
            arr(i, j) = 1
        Else
            arr(i, j) = arr(i - 1, j) + arr(i - 1, j - 1)
        End If
        Console.Write(arr(i, j) & " ")
    Next
    Console.WriteLine()
Next

控制台输出：

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另一种方法，只在内存中保留以前和当前的迭代：

Dim oldList As New List(Of Integer)({0, 1})
For line = 1 To 7
  Dim newList As New List(Of Integer)
  For i = 1 To oldList.Count - 1
    newList.Add(oldList(i - 1) + oldList(i))
  Next
  Debug.Print(String.Join(" ", newList))
  oldList.Clear()
  oldList.Add(0)
  oldList.AddRange(newList)
  oldList.Add(0)
Next

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要使用windows窗体执行此操作，您需要一个文本框、多行文本框和设计界面上的一个按钮

下面是生成它所需的代码

Imports System.Numerics 'this allows you to  use big integer

Public Class pascal_triangle


    Private Function factorial(ByVal k As Integer) As BigInteger

'big integer allows your proram compute for inputs of more than 22

        If k = 0 Or k = 1 Then

            Return 1

        Else

            Return k * factorial(k - 1)


        End If

    End Function



    Private Sub BtnGen_Click(sender As Object, e As EventArgs) Handles BtnGen.Click
        Dim nCr As Double

        Dim i, j, k As Integer


        Dim output As String

        output = ""

        j = Val(TxtColumn.Text)

        For k = 0 To j

            For i = 0 To k

                Dim fact, fact1, fact2 As BigInteger



                fact = factorial(k)

                fact1 = factorial(k - i)

                fact2 = factorial(i)

                nCr = fact / (fact1 * fact2)

                TxtOutput.Text += Str(nCr) & output





            Next

            TxtOutput.Text += vbCrLf

        Next



    End Sub


    Private Sub pascal_triangle_Load(sender As Object, e As EventArgs) Handles MyBase.Load

    End Sub
End Class

---

好的，我在一个控制台应用程序中实现了这一点，但是我想让它成为一种表单样式，用户输入行号。我现在正在自学VB，因此我试图理解这个例子。。你能简单解释一下它的工作原理吗？谢谢！我在上面添加了一些新代码，如果您能看一下，我会理解得更好。ThanksHow我会将其输出到标签，以及如何使用户输入的行数变为变量？我在上面添加了一些新代码，如果您能看一下，我会理解得更好。Thanks@DavidSalib：关于标签的输出，请先收集到StringBuilder中，然后将其转储到标签中，如下所示

label.Text=sb.ToString（）

。因此，您可以将

Debug.Print（String.Join（“，newList））

替换为

sb.AppendLine（String.Join（“，newList））

。7是要计算的行数，将其替换为CInt（yourInput.Text），并且不要忘记错误检查。

Imports System.Numerics 'this allows you to  use big integer

Public Class pascal_triangle


    Private Function factorial(ByVal k As Integer) As BigInteger

'big integer allows your proram compute for inputs of more than 22

        If k = 0 Or k = 1 Then

            Return 1

        Else

            Return k * factorial(k - 1)


        End If

    End Function



    Private Sub BtnGen_Click(sender As Object, e As EventArgs) Handles BtnGen.Click
        Dim nCr As Double

        Dim i, j, k As Integer


        Dim output As String

        output = ""

        j = Val(TxtColumn.Text)

        For k = 0 To j

            For i = 0 To k

                Dim fact, fact1, fact2 As BigInteger



                fact = factorial(k)

                fact1 = factorial(k - i)

                fact2 = factorial(i)

                nCr = fact / (fact1 * fact2)

                TxtOutput.Text += Str(nCr) & output





            Next

            TxtOutput.Text += vbCrLf

        Next



    End Sub


    Private Sub pascal_triangle_Load(sender As Object, e As EventArgs) Handles MyBase.Load

    End Sub
End Class