如果数组a(下标1到n)满足a(1)≤a(2)≤…≤a(i-1)≤a(i)≥a(i+1)≥…≥a(n),则称数组a是单峰的,并称a(i)是数组a的“峰顶”。下列程序段用于查找数组a中的“峰顶”,并返回该“峰顶”值。
Dim a( 1 To 10) As Integer
Function Search(L As Integer, R As Integer)
As Integer
M=(L+R)\2
If a(M) <a(M-1) And a(M) >a(M+1) Then
①
ElseIf a(M) >a(M-1) And a(M) >a(M+1) Then
②
ElseIf a(M) >a(M-1) And a(M) <a(M+1) Then
③
End If
End Function
Private Sub Command 1 click()
Label 1.caption=““峰顶”值是:” +Str(Search (1,10))
End Sub
上述程序中划线处可选语句为:
①Search=Search(M+1,R)
②Search=Search(L,M-1)
③Search=a(M)
则①②③处的语句依次是( )