Question

已知A1=0,A2=1,A3=2,A4=A1+2*A2+A3;A5=A2+2*A3+A4...求A23

Private Sub Form_Click()
Dim a As Long, b As Long, c As Long, d As Long, e As Long, f As Long, g As Long
a = 0: b = 1: c = 2
For e = 1 To 20
For f = 1 To 20
For g = 1 To 20
d = a + 2 * b + c
Next g
Next f
Next e
Print d
End Sub
------------------------调试，显示结果为4，显然不可能，我错在哪咯？----------------------------------------------------------

Answer 1

A3=2，也就是说.求A23
在循环体中,A4=A1+2*A2+A3，d恒等于a
+
2
*
b
+
c.，是你的程序没有实现上面的功能A1=0.，你的a,A2=1结果显然等于4;A5=A2+2*A3+A4、b

Answer 2

.结果显然等于4，是你的程序没有实现上面的功能A1=0,A2=1,A3=2,A4=A1+2*A2+A3;A5=A2+2*A3+A4...求A23

在循环体中，d恒等于a + 2 * b + c，也就是说，你的a、b、c三个变量并没有进行值的传递…….
Private Sub Command1_Click()
Dim a As Long, b As Long, c As Long, d As Long
a = 0: b = 1: c = 2
For i = 4 To 23
d = a + 2 * b + c
a = b
b = c
c = d
Next i
Print c
End Sub ,本来就是4的嘛,
一下子想不出关系来,只能先这样算了.

呵呵,楼上的已经做好了啊,没看到呢

Private Sub Command1_Click()
Dim a(23) As Long

a(1) = 0
a(2) = 1
a(3) = 2
For i = 4 To 23
a(i) = a(i - 3) + 2 * a(i - 2) + a(i - 1)

Next
Print a(23)

End Sub

Answer 3

结果显然等于4，是你的程序没有实现上面的功能A1=0,A2=1,A3=2,A4=A1+2*A2+A3;A5=A2+2*A3+A4...求A23

在循环体中，d恒等于a + 2 * b + c，也就是说，你的a、b、c三个变量并没有进行值的传递……

Answer 4

Private Sub Command1_Click()
Dim a As Long, b As Long, c As Long, d As Long
a = 0: b = 1: c = 2
For i = 4 To 23
d = a + 2 * b + c
a = b
b = c
c = d
Next i
Print c
End Sub ,本来就是4的嘛,
一下子想不出关系来,只能先这样算了.

呵呵,楼上的已经做好了啊,没看到呢

Private Sub Command1_Click()
Dim a(23) As Long

a(1) = 0
a(2) = 1
a(3) = 2
For i = 4 To 23
a(i) = a(i - 3) + 2 * a(i - 2) + a(i - 1)

Next
Print a(23)

End Sub

Answer 5

4 A1=0,A2=1,A3=2,A4=A1+2*A2+A3;A5=A2+2*A3+A4...求A23
,本来就是4的嘛,
一下子想不出关系来,只能先这样算了.

呵呵,楼上的已经做好了啊,没看到呢

Private Sub Command1_Click()
Dim a(23) As Long

a(1) = 0
a(2) = 1
a(3) = 2
For i = 4 To 23
a(i) = a(i - 3) + 2 * a(i - 2) + a(i - 1)

Next
Print a(23)

End Sub