s = "123456789"

g = ""

For i = 1 To 3

n = Len(s)

x = Int(Rnd() * n) + 1

g = g + Mid(s, x, 1)

s = Mid(s, 1, x - 1) + Mid(s, x + 1, n - x)

Next i

在程序执行时，若变量 x 的值依次为3,3,6，则最终变量g的值为（   ）

Private Sub Command1_Click()

  Dim a As Integer, b As Single

  a = Val(Text1.Text)

  b=3.14*a^2

  Text2.Text = "圆面积为:"+ b

End Sub

s = ""

For i = 1 To Len(Text1.Text)

   s = s + Mid(Text1.Text, Len(Text1.Text) - i + 1, 1)

Next i

若文本框Textl中输入“a1b2c3”,执行程序后，变量s的值为（  ）

请在划线处填入合适的代码

Private Sub Command1_Click()

  Dim s As String, k As Integer

  k = Val(Text2.Text)

  Label3.Caption=“对应的十进制数：”+Str(toD(s, k))

End Sub

Function toD(s As String, k As Integer) As Integer

  Dim ans As Integer, x As Integer

  ans = 0

  For i = 1 To Len(s)

    If Mid(s, i, 1) >= "A" And Mid(s, i, 1) <= "F" Then

      x = Asc(Mid(s， i, 1))- Asc(“A”)十 10

    Else

      x = Val(Mid(s, i, 1))

    End If

  Next i

End Function

n = 0

For i = 1 To Len(Text1.Text)

    c = Mid(Text1.Text, i, 1)

    If c >= "0" And c <= "9" Then m = 1 Else m = 2

    a(m) = a(m) + 1

    If a(m) = 1 Then n = n + 1

Next i

数组a各元素的初始值都为0，文本框Textl的内容为“Luck2018”。执行程序后，变量n的值为

   from math import *

def dist(x1, y1, x2, y2):

    length = sqrt((int(x1) - int(x2))**2 +    ①     )

    return length

a = input("请输入各点的坐标：")    # 如“2,3,4,5”则表示坐标点（2,3）和（4,5）

b = a.split(",")

if len(b) % 2 != 0:

    print("输入的坐标有误！")

else:

    s = 0

    for i in range(0,    ②      , 2):

        s = s +     ③    

print("折线的长度为：", s)