vb.net隨機數學

Question

有誰知道我會隨機產生一個基本的數學問題，其答案總是1,2,3或4. 因此，例如使用兩個隨機數8和4我可能會顯示的問題：

8/4，從而在此情況下，答案是2。其它實施例：2 * 2，8/8，4 + 0等等，但 答案總是在範圍爲1〜4。 由於

Answer 1

我是po點擊下面的想法。

如果您只想使用正整數（在此示例中，counterPartNumerator可能不是），則需要進行一些調整。

玩得開心！

Private _possibleNumerators() As Integer = {2, 4, 8, 12, 15, 20, 25, 32, 40} ' Random numbers I arbitrarily chose 
Private _possibleResults() As Integer = {1, 2, 4, 8} 
Friend Enum Operation As Integer 
    Add = 0 
    Subtract = 1 
    Multiply = 2 
    Divide = 3 
End Enum 

Private _randomGen As New Random 

Public Sub ShowArithmeticExpression() 
    Dim randomNumerator As Integer = GetRandom(_possibleNumerators) 
    Dim counterPartNumerator As Decimal 
    Dim randomDesiredResult As Integer = GetRandom(_possibleResults) 
    Dim randomOperation As Operation = GetRandom([Enum].GetValues(GetType(Operation))) 
    Dim operationSymbol As String 

    ' Find counterPartNumerator 
    Select Case randomOperation 
     Case Operation.Add 
      counterPartNumerator = randomDesiredResult - randomNumerator 
      operationSymbol = "+" 
     Case Operation.Subtract 
      counterPartNumerator = randomNumerator - randomDesiredResult 
      operationSymbol = "-" 
     Case Operation.Multiply 
      counterPartNumerator = randomDesiredResult/randomNumerator 
      operationSymbol = "*" 
     Case Operation.Divide 
      counterPartNumerator = randomNumerator * randomDesiredResult 
      operationSymbol = "/" 
    End Select 

    Console.WriteLine(String.Format("{0} {1} {2} = ?", randomNumerator, operationSymbol, counterPartNumerator)) 
    Console.WriteLine(String.Format("Result = {0}", randomDesiredResult)) 
End Sub 

Private Function GetRandom(numberSet As Integer()) As Integer 
    Dim minValue, maxValue As Integer 

    ' Could simplify this using Linq. Eg: minValue = numberSet.Min() : maxValue = numberSet.Max() 
    For Each number In numberSet 
     If number < minValue Then minValue = number 
     If number > maxValue Then maxValue = number 
    Next 

    While True 
     Dim valueReturn As Integer = _randomGen.Next(minValue, maxValue) 
     If numberSet.Contains(valueReturn) Then 
      Return valueReturn 
     End If 
    End While 

    Return -1 
End Function 

Answer 2

試試以下代碼

Dim xGenerator As System.Random = New System.Random() 
     Dim xTemp As Integer = 0 
     Dim c As Integer = 0 
     Dim xRndNo As New List(Of Integer) 

     While Not xRndNo.Count = 2 

      xTemp = xGenerator.Next(0, 9) 
      If c = 0 Then 
       xRndNo.Add(xTemp) 
      Else 
       If (xRndNo.Item(0) + xTemp) Or (xRndNo.Item(0) - xTemp) Or (xRndNo.Item(0) * xTemp) Or (xRndNo.Item(0)/xTemp) <= 4 And ((xRndNo.Item(0) + xTemp) Or (xRndNo.Item(0) - xTemp) Or (xRndNo.Item(0) * xTemp) Or (xRndNo.Item(0)/xTemp)) > 0 Then 
        xRndNo.Add(xTemp) 
       End If 
      End If 
      c = +1 
     End While