amin = a(1): amax = a(1)
i = 2: j = 9
Do While i <= j
If a(i) > a(j) Then
Else
End If
i = i + 1: j = j - 1
Loop
Text1.Text = Str(amin) + "," + Str(amax)
上述程序段中方框处可选语句为:
①If a(j) > amax Then amax = a(j)
②If a(j) < amin Then amin = a(j)
③If a(i) < amin Then amin = a(i)
④If a(i) > amax Then amax = a(i)
则方框处语句依次可为( )