Looping Question

Hi guys...

Our class just got into looping and list boxes with VB.Net, and I got a question that I am stuck on and appreciate any help!

Write a program that will display all the numbers between 1 and 100 that are part of the Fibonacci sequence. The Fabonacci sequence begins 1,1,2,3,5,8,..., where each new number in the sequence is found by adding the previous two numbers in the sequence. Display your results in a list box or a text box with a multilane property set to True.


Regards

I have no idea on VB.Net so I won't post code...

To start the sequence you need a seed, which is two ones (1,1). Store those in an array at index 0 and 1. Start looping (counter starts at 1, since that's currently the last array index used) . At each loop add array index = counter and array index = counter - 1, if sum is less than 100 then append sum to array index = counter + 1. If sum is equal or greater than 100 then stop the loop.

Transfer the array values to a listbox or multiline textbox.

Up to you if you'll use dynamic arrays.

VB Code:

dim LastNumber as integer
dim PreviousNumber as integer
dim CurrentNumber as integer
 
listbox1.clear
listbox1.additem 1
 
lastnumber=1
previousnumber=0
currentnumber=0
 
while currentnumber<=100
  currentnumber=previousnumber+lastnumber
  listbox1.additem currentnumber
  previousnumber=lastnumber
  lastnumber=currentnumber
wend

Not in front of VB, so I can't test this, but it looks ok to me.
How many marks do you get for this question - I think you owe me some!

The way you had it included 144 ;)

VB Code:

Dim LastNumber As Integer
Dim PreviousNumber As Integer
Dim CurrentNumber As Integer
 
listbox1.Clear
listbox1.AddItem 1
 
LastNumber = 1
PreviousNumber = 0
CurrentNumber = 0
 
While CurrentNumber <= 100
  CurrentNumber = PreviousNumber + LastNumber
  If CurrentNumber > 100 Then GoTo SkipLoop
  listbox1.AddItem CurrentNumber
  PreviousNumber = LastNumber
  LastNumber = CurrentNumber
Wend
SkipLoop:

I do hope that this'll work in .NET too (ie, it was testing in VB6)

So the seed is 0,1?

Why not put the test at the end of the loop since your bound to go through it at least once.

Thanx guyz..I really appreciate it! I will give it a shot and see how it turns out.


Buzby, This is actually like 3 points on a worksheet but it was killing me so I had to find the answer! ;)

Make sure you dont use GoTos. They are evil :D

Quote:

---

Originally posted by jemidiah
The way you had it included 144 ;)

VB Code:

Dim LastNumber As Integer
Dim PreviousNumber As Integer
Dim CurrentNumber As Integer
 
listbox1.Clear
listbox1.AddItem 1
 
LastNumber = 1
PreviousNumber = 0
CurrentNumber = 0
 
While CurrentNumber <= 100
  CurrentNumber = PreviousNumber + LastNumber
  If CurrentNumber > 100 Then GoTo SkipLoop
  listbox1.AddItem CurrentNumber
  PreviousNumber = LastNumber
  LastNumber = CurrentNumber
Wend
SkipLoop:

I do hope that this'll work in .NET too (ie, it was testing in VB6)

---

Wends are gone in .net if i am not wrong

Quote:

---

Originally posted by PT Exorcist
Wends are gone in .net if i am not wrong

---

I can't find any reference to that keyword in my book, so yeah they arn't their anymore.

Though from the code that was posted using it, it seems very useless......

just change the wend by next

i think that'll make the trick

Quote:

---

Originally posted by PT Exorcist
just change the wend by next

i think that'll make the trick

---

Why??

What does Wend even do? Does it go back to the top of the loop? Or stop it?

does the same as next in a for loop

Quote:

---

Originally posted by PT Exorcist
does the same as next in a for loop

---

But it's a while loop, next and wend are both useless for a while loop....

meh

omg

its just a FLAG to the compiler know where the while beggins and ends

While..Wend are my loop of choice (probably just being stubborn to be honest).. the replacement is Do While.. Loop

VB Code:

dim LastNumber as integer
dim PreviousNumber as integer
dim CurrentNumber as integer
 
listbox1.clear
listbox1.additem 1
 
lastnumber=1
previousnumber=0
currentnumber=0
 
do while currentnumber<=100
  currentnumber=previousnumber+lastnumber
  listbox1.additem currentnumber
  previousnumber=lastnumber
  lastnumber=currentnumber
loop

or you could do

VB Code:

do
  currentnumber=previousnumber+lastnumber
  listbox1.additem currentnumber
  previousnumber=lastnumber
  lastnumber=currentnumber
loop until currentnumber>100