Question

vb题目 下面程序，单击Comamd1 按钮，Text1中输入“12123152”，则窗体显示的第二行为什么是：123

下面程序，单击Comamd1 按钮，Text1中输入“12123152”，则窗体显示的第二行为什么是 123
Option Explicit
Option Base 1
Private Sub Command1_Click()
Dim s As String, i As Integer, a() As Integer
s = Text1.Text
For i = 1 To Len(s)
ReDim Preserve a(i)
a(i) = Val(Mid(s, i, 1))
Next i
Call Sub1(a)

End Sub

Private Sub Sub1(a() As Integer)
Dim i As Integer, j As Integer, k As Integer
i = 2
Do Until i >= UBound(a)
k = i - 1
Do Until a(i - 1) > a(i)
i = i + 1
Loop
For j = k To i - 1
Print a(j)
Next j
Print
i = i + 1
Loop
End Sub

Answer 1

总参数为12123152
长度为8
i = 2
第一次循环
k = 1
a1<a2
i = 3
a2>a3
跳出
j=1到2
打印a (1), a(2)
打印换行
i = 3 + 1 = 4
第二次循环
k = 3
a3<a4
i = 4 + 1 = 5
a4<a5
i = 5 + 1 = 6
a5>a6跳出
打印a3 , a4，a5
打印换行

a3=1,a4=2,a5=3