(加试题)所谓双向排序是在一遍加工中先从上到下把最大的元素送到最下的位置,再从下到上把最小的元素送到最上的位置。实现上述功能的vb代码如下:
Dim a(1 to 100) as integer
Const n=10
Private Sub form_load()
’生成n个随机数,存储在数组a中,代码略
End Sub
Private Sub command1_click()
Dim I as integer,j as integer
For
① For j=i to n-i
If a (j)>a(j+1) then
t=a(j):a(j)=a(j+1):a(j+1)=t
End If
Next j
For
②If a(j)<a(j-1) then
t=a(j):a(j)=a(j-1):a(j-1)=t
End If
Next j
Next i
for i=1 to n
List2.additem str(a(i))
Next i
End Sub
程序中①②处最合适的语句是( )
A.① i=1 to n-1 ②j=n to i+1 step -1 |
B.① i=1 to n\2 ②j=n-i to i+1 step -1 |
C.① i=1 to n\2 ②j=n to i+1 step -1 |
D.① i=1 to n-1 ②j=n-i to i+1 step -1 |