有關vb既程式~唔識解~

For q = 0 To 50
a1 = Int(Rnd() * 14)
a2 = Int(Rnd() * 14)
Dim temp As Integer
temp = x(a1)
x(a1) = x(a2)
x(a2) = temp
Next
y(0) = x(0) + x(1)
y(1) = x(2) + x(3)
y(2) = x(4) + x(5)
y(3) = x(6) + x(7)
y(4) = x(8) + x(9)
lstquestion.Items.Add(" ? + " & x(0) & " = " & y(0))
lstquestion.Items.Add(" ? + " & x(2) & " = " & y(1))
lstquestion.Items.Add(" ? + " & x(4) & " = " & y(2))
lstquestion.Items.Add(" ? + " & x(6) & " = " & y(3))
lstquestion.Items.Add(" ? + " & x(8) & " = " & y(4))
lstquestion.SelectedItem = (" ? + " & x(0) & " = " & y(0))
txtanswer.Focus()
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