How to Add 90 digits No

[aky]

IN c++ i added a 90 digits no around 5 lakh times .It took around 6 sec .
and in visual Basic around 2 mins.
can anyone send me the Vb code for adding 90 digits NO taking less time

[Alejandro Ochoa]

Post your code to see if it can be improved...

[aky]

Hi
Here is the code

Dim strFirstNo as string
Dim strSecondNo as string
Dim strResult as string
Dim nCtr as Long
Dim nCarryForwrd as Long
Dim nAddition as Long
Dim nFirstNoLen as Long
Dim nSecondNoLen as Long
Dim nCarryForward as Long

strFirstNo = "1212345678902345678903456789456789043567890876764536576786564453543467"
strSecondNo = "1212345678902345678903456789456789043567890876764536576786564453543467"

nFirstNoLen = len(strFirstNo)
nSecondNoLen = len(strSecondNo)

nCtr = 0
nCarryForwrd = 0
Dim ncount as Long

Dim strStarttime as string
Dim strEndtime as string

strStarttime = Now
for ncount = 1 to 50000
strResult = ""

nFirstNoLen = len(strFirstNo)
nSecondNoLen = len(strSecondNo)
While nFirstNoLen > 0
nAddition = Val(mid(strFirstNo, nFirstNoLen, 1)) + Val(mid(strSecondNo, nSecondNoLen, 1)) + nCarryForward
strResult = Right(CStr(nAddition), 1) & strResult
If nAddition > 9 then
nCarryForward = Val(Left(CStr(nAddition), 1))
End If
nFirstNoLen = nFirstNoLen - 1
nSecondNoLen = nSecondNoLen - 1
Wend
next

strEndtime = Now
MsgBox strStarttime + "End time = " & strEndtime




Waiting for response

[Cimperiali]

to work (a little) faster with strings, substitute
Right with Right$
Left with Left$
mid with mid$
However, I do not think this will enanche it a lot...

Cesare Imperiali


Special thanks to Lothar "the Great" Haensler, Tom Archer, Chris Eastwood, TCartwright, Bruno Paris
and all the other wonderful people who made and make Codeguru a great place.
Come back soon, you Gurus.

The Rater

[Cimperiali]

'I did some tests and found out it is mid$ function who slow this down.
'Moreover, your code is not all right...(you did not reset the nCarryForward)
'I tried with array, and the following seems a little faster (1 min instead
' of 2 min, even if there are a lot of operations)
'Have a try

Dim arr1() as Integer
Dim arr2() as Integer
Dim arrResult() as Integer
Dim tmpval as Integer
Dim strStarttime as string, strEndtime as string
Dim lngCount as Long
Dim intUbArray as Integer
Dim tmpArr as Variant
Dim strResultString as string
Screen.MousePointer = vbHourglass
'fill with values
tmpArr = Array(1, 2, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 2, 3, 4, 5, 6, 7, 8, 9, 0, 3, 4, 5, 6, 7, 8, 9, 4, 5, 6, 7, 8, 9, 0, 4, 3, 5, 6, 7, 8, 9, 0, 8, 7, 6, 7, 6, 4, 5, 3, 6, 5, 7, 6, 7, 8, 6, 5, 6, 4, 4, 5, 3, 5, 4, 3, 4, 6, 7)
ReDim arr1(UBound(tmpArr))

for lngCount = 0 to UBound(tmpArr)
arr1(lngCount) = tmpArr(lngCount)
next

Erase tmpArr
tmpArr = Array(1, 2, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 2, 3, 4, 5, 6, 7, 8, 9, 0, 3, 4, 5, 6, 7, 8, 9, 4, 5, 6, 7, 8, 9, 0, 4, 3, 5, 6, 7, 8, 9, 0, 8, 7, 6, 7, 6, 4, 5, 3, 6, 5, 7, 6, 7, 8, 6, 5, 6, 4, 4, 5, 3, 5, 4, 3, 4, 6, 7)
ReDim arr2(UBound(tmpArr))
for lngCount = 0 to UBound(tmpArr)
arr2(lngCount) = tmpArr(lngCount)
next
Erase tmpArr
strStarttime = Now
for lngCount = 1 to 50000
'perform sum

If UBound(arr1) > UBound(arr2) then
ReDim arrResult(UBound(arr1) + 1) 'dimension it and fill with 0
else
ReDim arrResult(UBound(arr2) + 1)
End If
for intUbArray = UBound(arr1) to 0 step -1
tmpval = arr1(intUbArray) + arr2(intUbArray)
If tmpval > 9 then
arrResult(intUbArray + 1) = CInt(Right$(CStr(tmpval), 1)) + arrResult(intUbArray + 1)
arrResult(intUbArray) = CInt(Left$(CStr(tmpval), 1)) + arrResult(intUbArray)
else
arrResult(intUbArray + 1) = tmpval + arrResult(intUbArray + 1)
End If
next intUbArray
next lngCount

for intUbArray = 0 to UBound(arrResult)
strResultString = strResultString & CStr(arrResult(intUbArray))
next intUbArray
If Left$(strResultString, 1) = "0" then
strResultString = Right$(strResultString, len(strResultString) - 1)
End If
strEndtime = Now
Screen.MousePointer = vbDefault
MsgBox strStarttime & vbCrLf & "End time = " & strEndtime & vbCrLf & strResultString






Special thanks to Lothar "the Great" Haensler, Tom Archer, Chris Eastwood, TCartwright, Bruno Paris
and all the other wonderful people who made and make Codeguru a great place.
Come back soon, you Gurus.

The Rater

[shree]

Assigning a string directly to a byte array is much faster than meddling with variant arrays.

private Sub Command1_Click()
Dim ByteArr() as Byte
Dim i as Integer
Dim strng as string
strng = "1212345678902345678903456789456789043567890876764536576786564453543467"
ByteArr = strng
for i = 0 to UBound(ByteArr) step 2
print ByteArr(i);
next
End Sub

[deghost]

hi, i found your task interesting and thought i'd give it a try, i don't understand what's all the fuzz about 2 min, it works in less than a sec for me. give it a try, maybe i didn't understand something... this is it:

Dim tmpArr as Variant
Dim n1() as Long
Dim n2() as Long
Dim sum() as Long
Dim s1 as Integer
Dim s2 as Integer
Dim ltemp as Long
Dim lLoop as Integer
Dim x as Long
Dim t as Long
'!!! you have to enter the number this way!:
tmpArr = Array(111111, 222222, 333333, 444444, 555555, 666666, 777777, 888888, 999999, 0)
'!!! it is also backwards, (111111 are the least segn. digits)
s1 = UBound(tmpArr) '!!! i used them in the same size 4 comfort, i don't use s2 (size2)
ReDim n1(s1)
for lLoop = 0 to s1
n1(lLoop) = tmpArr(lLoop)
next lLoop
Erase tmpArr
tmpArr = Array(111111, 333333, 555555, 222222, 444444, 666666, 0, 777777, 888888, 999999)
ReDim n2(s1)
for lLoop = 0 to s1
n2(lLoop) = tmpArr(lLoop)
next lLoop
Erase tmpArr

ReDim sum(s1 + 1)
t = Now
for lLoop = 0 to s1
x = sum(lLoop)
sum(lLoop) = (x + n1(lLoop) + n2(lLoop)) Mod 1000000
sum(lLoop + 1) = (x + n1(lLoop) + n2(lLoop)) \ 1000000
next lLoop
t = Now - t



the sum array gets the number in the same way as the input (in XXXXXX mask)
it's really easy to print it! just print the sum array cells 1 by 1...*:)

----------
The @host is everywhere!
----------

[aky]

HI Deghost

I tried it this way .
repeat the whole addition
in loop (5 lakh times )
then see what happens .it should take
time more than 2 mins .
thanx for response

[Strat]

This looks suspiciously like one of those "Why can't VB do something as well as C++", but I tried playing around with it anyway. I was able to get the time down to about 30 seconds (on my machine) using the following code:

public Sub StringAdd()

Dim strFirstNo as string
Dim strSecondNo as string
Dim strResult as string
Dim nAddition as Long
Dim nCarryForward as Integer
Dim ncount as Long
Dim strStarttime as string
Dim strEndtime as string
Dim First() as Integer
Dim Second() as Integer
Dim i as Integer

strFirstNo = "1212345678902345678903456789456789043567890876764536576786564453543467"
strSecondNo = "1212345678902345678903456789456789043567890876764536576786564453543467"
ReDim First(len(strFirstNo) - 1)
ReDim Second(len(strSecondNo) - 1)

for i = 0 to len(strFirstNo) - 1
First(i) = mid(strFirstNo, i + 1, 1)
next i

for i = 0 to len(strSecondNo) - 1
Second(i) = mid(strSecondNo, i + 1, 1)
next i

strStarttime = Now

for ncount = 1 to 50000
strResult = ""
for i = 0 to UBound(First)
nAddition = First(i) + Second(i) + nCarryForward
strResult = Right(nAddition, 1) & strResult
If nAddition > 9 then
nCarryForward = Left(nAddition, 1)
else
nCarryForward = 0
End If
next
next

strEndtime = Now
MsgBox "Start time = " & strStarttime & vbCrLf & "End time = " & strEndtime

End Sub

[Kdev]

With your code it took me 159 seconds to process, with the following code it took me 10 seconds to process.

NOTE: The - 96 and the + 48 are ascii adjustments so that the math is done using the integers and stored as the ascii values for the string representation of the numbers.

Dim strFirstNo as string
Dim strSecondNo as string
Dim strFiller as string
Dim strResult as string
Dim nAddition as Long
Dim nCarryForward as Long
Dim ByteArr1() as Byte
Dim ByteArr2() as Byte
Dim ByteArrResult() as Byte
Dim i as Integer

strFirstNo = "1212345678902345678903456789456789043567890876764536576786564453543467"
strSecondNo = "1212345678902345678903456789456789043567890876764536576786564453543467"

If len(strFirstNo) > len(strSecondNo) then
strFiller = Space(len(strFirstNo) - len(strSecondNo))
strFiller = Replace(strFiller, " ", "0")
strSecondNo = strFiller & strSecondNo
ElseIf len(strSecondNo) > len(strFirstNo) then
strFiller = Space(len(strSecondNo) - len(strFirstNo))
strFiller = Replace(strFiller, " ", "0")
strFirstNo = strFiller & strFirstNo
End If

ByteArr1 = strFirstNo
ByteArr2 = strSecondNo
ReDim ByteArrResult(UBound(ByteArr1))

nCarryForward = 0

Dim ncount as Long
Dim strStarttime as string
Dim strEndtime as string

strStarttime = Now
for ncount = 1 to 50000
ReDim ByteArrResult(UBound(ByteArr1))

for i = UBound(ByteArr1) - 1 to 0 step -2
nAddition = ByteArr1(i) + ByteArr2(i) - 96 + nCarryForward
ByteArrResult(i) = 48 + (nAddition Mod 10)
nCarryForward = (nAddition \ 10)
next i

strResult = ByteArrResult
If nCarryForward > 0 then strResult = Str(nCarryForward) & strResult
next ncount
strEndtime = Now

MsgBox "Start time = " & strStarttime & vbCrLf & "End time = " & strEndtime & _
vbCrLf & "Duration: " & 86400 * (CDate(strEndtime) - CDate(strStarttime)) & vbCrLf & _
"Result: " & strResult



-K

[Kdev]

You can shave off 1 more second of this code if you take out the Redim statement that is inside of the For loop. This statement is unneccessary since on subsequent iterations you overwrite every element anyway.

-K

[shree]

Did you run your program through the environment or after making an exe

A program that contains many loops runs much faster in an exe, the speed(in the case of VB6) being comparable with C, other things remaining same.

If you don't already know,
For improvement in speed, go to the compile tab in Project|Properties and click Advanced Optimizations. Check all options. But do make sure that you are not exceeding array bounds, or such things, if you don't want to see the blue screen too often.