vb程序Dim a(1 To 20) As Integer,i As Integer,j As Integer

vb程序Dim a(1 To 20) As Integer,i As Integer,j As Integer
Dim a(1 To 20) As Integer,i As Integer,j As Integer
Private Sub Command1_Click()
Dim a(1 To 20) As Integer
For j = 1 To 2
For i = 1 To 10
a(i) = Int(Rnd * 21) + 20
Text1 = Text1 & Str(a(i))
Next i
Text1 = Text1 & vbCrLf
Next j
End Sub
Private Sub Command2_Click()
Dim b(20 To 40) As Integer
a(i) = Int(Rnd * 21) + 20
b(a(i)) = 0
For i = 1 To 20
b(a(i)) = b(a(i)) + 1
Text2 = b(a(i)) & vbCrLf
Next i
End Sub
为什么数组越界 哪出错啦
这个 程序要实现的是 产生20个20—40间的两位随机数 统计不同数据出现的次数