Ad:

C++ Discussion Thread
Unsolved
Views: 599

Page 1
2
Next

You are currently viewing page 1 of this multi-page discussion thread

Mar 23rd, 2009

C++ Calculations

Expand Post »

Hello All
I am having some problems with a C++ class that i am taking and after looking around on the web I am still lost.
The assignment that I am working on right now is as follows:

(Toggle Plain Text)

Two numbers are entered in from the keyboard. If the
larger number is odd, the smaller number is added to an accumulator. Then the larger number
is integer divided by two and the smaller number is doubled. Again if the larger number's
division is odd, the smaller number's doubling is added to an accumulator. lf the larger number
is even, nothing is added to the accumulator. This is repeated until the large number
sequence equals zero. The accumulator now holds the multiplication answer.
Write a program using functions, that will accomplish this task. Repeat until the user wishes to stop.
lt is not necessary to display the accumulation work as shown in the examples.
Output is to the screen and printer and should look like:
Your Name Class # Date & Time
XXXX times XXXX by conventional math = XXXXXXX
XXXX times XXXX by Zoo's method = XXXXXXX
Example 1) 75 x 23 = 1725
Larger 			Smaller 			Add to Accumulator
75			 23 				23
37 			46 				46
18 			92 				O
9 			184 				184
4 			368				 O
2 			736 				O
1 			1472 				1472
1725(TOTAL & PRODUCT)


Example 2) 
122 x 251 = 30622
Larger 		Smaller 			Add to Accumulator
251 		122 					122
125 		244 					244
62 		488 					O
31 		976 					976
15 		1952 					1952
7 		3904 					3904
3 		7808 					7808
1 		15616					 15616
30622(TOTAL & PRODUCT)

If anyone could point me in a good direction i would be most great full
Thanx

Similar Threads

Trouble writing code for arithmetic calculations of complex numbers in C++
Calculations, Variables and Constants - Please help in VB.NET
Price Calculations in C#
random number generator and calculations in Java
Calculations in C++

kuru225

Reputation Points: 10

Solved Threads: 0

Newbie Poster

Offline

5 posts
since Mar 2009

Permalink

Mar 23rd, 2009

Re: C++ Calculations

>>If the larger number is odd,

what happens if the larger number is even ?

Last edited by Ancient Dragon; Mar 23rd, 2009 at 3:50 pm.

Ancient Dragon

Sponsor

Team Colleague

Featured Poster

Reputation Points: 5608

Solved Threads: 2282

Retired and Enjoying Life

Offline

21,953 posts
since Aug 2005

Permalink

Mar 23rd, 2009

Re: C++ Calculations

Ancient, thanks for the quick reply.
if the larger number is even then the accumulator is '0'

If you have any ideas on how the logic would go your help would be most appreciated
thanks

kuru225

Reputation Points: 10

Solved Threads: 0

Newbie Poster

Offline

5 posts
since Mar 2009

Permalink

Mar 23rd, 2009

Re: C++ Calculations

Write it out by hand. It might start like this:

C++ Syntax (Toggle Plain Text)
enter two numbers.
calculate the product of the two numbers.
determine which number is larger, call it A, and call the other number B.  
use an accumulator, initialzed to zero
as long as A is above zero
  if A is odd 
    add B to accumulator
  divide A by 2 using integer math (means all remainders are dropped)
  //etc
enter two numbers.
calculate the product of the two numbers.
determine which number is larger, call it A, and call the other number B.  
use an accumulator, initialzed to zero
as long as A is above zero
  if A is odd 
    add B to accumulator
  divide A by 2 using integer math (means all remainders are dropped)
  //etc

Lerner

Reputation Points: 718

Solved Threads: 373

Nearly a Posting Maven

Offline

2,253 posts
since Jul 2005

Permalink

Mar 23rd, 2009

Re: C++ Calculations

and if A is initially even, don't do anything.

Ancient Dragon

Sponsor

Team Colleague

Featured Poster

Reputation Points: 5608

Solved Threads: 2282

Retired and Enjoying Life

Offline

21,953 posts
since Aug 2005

Permalink

Mar 23rd, 2009

Re: C++ Calculations

if A is even at anypoint, whether initially or not, then don't add B to accumulator, but you still need to divide A by 2 using integer math and double B. So if A = 44 and B = 11;

C++ Syntax (Toggle Plain Text)
A    B    Total Accumulated so far
11     0
22     0
44     44
 88     132
 176   132
 352   484
A    B    Total Accumulated so far
11     0
22     0
44     44
 88     132
 176   132
 352   484

Lerner

Reputation Points: 718

Solved Threads: 373

Nearly a Posting Maven

Offline

2,253 posts
since Jul 2005

Permalink

Mar 23rd, 2009

Re: C++ Calculations

AD: If the (originally) larger number is even you simply don't add the (originally) smaller one to the accumulator. Since "odd" just means that the one's bit is set, it's essentially binary mutiplication using shifts (division by 2) and adds.

kuru: Have you written a program before? Do you have an attempt for this one? Anything?

nucleon

Reputation Points: 163

Solved Threads: 91

Posting Pro in Training

Offline

476 posts
since Oct 2008

Permalink

Mar 24th, 2009

Re: C++ Calculations

Nuc: so if i have you right, i could just write an 'if' statement saying:

(Toggle Plain Text)

if(numA<numB)
   numA / 2.0
else
   accum +=numA

and then i could wrap this in a function for later use

kuru225

Reputation Points: 10

Solved Threads: 0

Newbie Poster

Offline

5 posts
since Mar 2009

Permalink

Mar 24th, 2009

Re: C++ Calculations

Ok
i have been tinkering around with the coding of this, and i think there is a problem with this function i have
could someone give me there input

(Toggle Plain Text)

void getnums()
{
     
  int numA, numB, x, result;
  cout << "Your two numbers to multiply are?"<<endl;
  cin >> numA >> numB;

  if (numB < numA)
  {
    x +=numA;
    numA = numB;
    numB = x;
  }
   
  result = process( numA, numB);

  
  cout << numA << " times " << numB<< " by conventional math = " << (numA * numB) <<endl;
  cout << numA << " times " << numB<< " by Zoo's method = " << result <<endl;
  
}

the function works fine if numA starts smaller then numB but if numB is smaller then numA it sort of goes to the crapper
any help would be welcomed
thanx

Last edited by kuru225; Mar 24th, 2009 at 12:36 pm.

kuru225

Reputation Points: 10

Solved Threads: 0

Newbie Poster

Offline

5 posts
since Mar 2009

Permalink

Mar 24th, 2009

Re: C++ Calculations

Problem is that x is not initialized to zero (I take that you simply want to swap the values).

You might have it a bit simpler like ...

C++ Syntax (Toggle Plain Text)
if (numB < numA)
{
    // use x only inside the if-block
    int x = numA;
    numA = numB;
    numB = x;
}
if (numB < numA)
{
    // use x only inside the if-block
    int x = numA;
    numA = numB;
    numB = x;
}

mitrmkar

Reputation Points: 1105

Solved Threads: 389

Posting Virtuoso

Offline

1,714 posts
since Nov 2007

Page 1
2
Next

This thread is more than three months old

No one has posted to this discussion for at least three months. Please let old threads die and do not reply to them unless you feel you have something new and valuable to contribute that absolutely must be added to make the discussion complete. Otherwise, please start a new thread in this forum instead.

Previous Thread in C++ Forum Timeline: Help with queues

Next Thread in C++ Forum Timeline: help ! Copy elements from 1 dimentional to 2 dimentional array

DaniWeb Message

Cancel Changes

User Name
Password