DaniWeb Forum Index > Software Development > C++

C++ RSS

How to count the elements of an array?

Please support our C++ advertiser: Intel Parallel Studio Home

•

Join Date: Apr 2009

Posts: 12

Reputation: super.mina has a little shameless behaviour in the past

Solved Threads: 0

super.mina super.mina is offline

Offline

Newbie Poster

How to count the elements of an array?

Apr 24th, 2009

If i have an array like that
int x[100]={1,0,3};

so only i have 3 elements and the rest of the array is zero, how can i count the number of elements in a larger one ..

•

Join Date: Apr 2008

Posts: 59

Reputation: Dannyo329 is an unknown quantity at this point

Solved Threads: 6

Dannyo329

Offline

Junior Poster in Training

Re: How to count the elements of an array?

Apr 24th, 2009

Do you mean to check how many elements there are in an array?

C programmers will get smashed by C++ programmers.

•

Join Date: Apr 2009

Posts: 12

Reputation: super.mina has a little shameless behaviour in the past

Solved Threads: 0

super.mina super.mina is offline

Offline

Newbie Poster

Re: How to count the elements of an array?

Apr 24th, 2009

I want to know how many elements in the array, not the size of the array...
E.g:

int x[1000]={1,22,3,54,7,89,1,0,0,1,2}
Number of elements = 11

is there any possible way to that.

•

Join Date: Apr 2008

Posts: 59

Reputation: Dannyo329 is an unknown quantity at this point

Solved Threads: 6

Dannyo329

Offline

Junior Poster in Training

Re: How to count the elements of an array?

Apr 24th, 2009

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
int array[10]={1,5,6,2,4,5,7,8,5};
 
    int n=0;
    int p;
    while (p!= '\0')
    {
                n++;
                p = array[n];
    }    
 
    cout << "There are "<<n-1 << " elements in the array.";
int array[10]={1,5,6,2,4,5,7,8,5};

    int n=0;
    int p;
    while (p!= '\0')
    {
                n++;
                p = array[n];
    }    

    cout << "There are "<<n-1 << " elements in the array.";

You shorten the code but its basically how you do it.

Last edited by Dannyo329; Apr 24th, 2009 at 5:05 am.

C programmers will get smashed by C++ programmers.

•

Join Date: Apr 2009

Posts: 12

Reputation: super.mina has a little shameless behaviour in the past

Solved Threads: 0

super.mina super.mina is offline

Offline

Newbie Poster

Re: How to count the elements of an array?

Apr 24th, 2009

This isn't working when i have for example the following array:

int x[100]={1,2,3,0,3,5,4,1};
The actual number of elements is 8,
but he will display 4

•

Join Date: Apr 2008

Posts: 59

Reputation: Dannyo329 is an unknown quantity at this point

Solved Threads: 6

Dannyo329

Offline

Junior Poster in Training

Re: How to count the elements of an array?

Apr 24th, 2009

Edited the code, try again,

C programmers will get smashed by C++ programmers.

•

Join Date: Oct 2006

Posts: 2,912

Reputation: niek_e has a reputation beyond repute

Solved Threads: 303

niek_e

Offline

Cenosillicaphobiac

Re: How to count the elements of an array?

Apr 24th, 2009

•

Originally Posted by Dannyo329

Edited the code, try again,

It will still fail. You are using P, but it's not initialized to anything.
Also 'n' will start at element 1, not 0
Also '\0' is the termination-character for CHAR- arrays, not INT.

@OP:
You could initialize your entire array to -1 if you only need positive numbers and then check when the first value is < 0, that'll give you the number of ints.
Or you could use a counter to keep track of the number of ints.
Or you could use a vector<int>

Could you tell us why you need this functionality?

Last edited by niek_e; Apr 24th, 2009 at 6:02 am.

Dear signature-spammers,

•

Join Date: Oct 2007

Posts: 793

Reputation: siddhant3s has much to be proud of

Solved Threads: 135

siddhant3s siddhant3s is offline

Offline

Master Poster

Re: How to count the elements of an array?

Apr 24th, 2009

>>Edited the code, try again,
Sorry, OP is right. x[100]={1,2,3,0,3,5,4,1}; will print 2 elements

To the OP:
You cannot !. Yes you cannot. However surprise it may bring to you, the truth is you really you cannot.
Thats why most of functions dealing with int array often asks you to enter the length of the array as one of the argument.
You will have to track the length of the array yourself.

Edit: Niek, I don't know why I couldn't see you editing, but the fact is that my "viewing list" at the bottom of page told me that no one was replying to the thread while I was.

Last edited by siddhant3s; Apr 24th, 2009 at 6:14 am.

Siddhant Sanyam
(Not posting much)
Migrate to Standard C++ :When to tell your C++ Code is Non-Standard.
Please Read before posting: How To Ask Questions The Smart Way

•

Join Date: Oct 2006

Posts: 2,912

Reputation: niek_e has a reputation beyond repute

Solved Threads: 303

niek_e

Offline

Cenosillicaphobiac

Re: How to count the elements of an array?

Apr 24th, 2009

•

Originally Posted by siddhant3s

Edit: Niek, I don't know why I couldn't see you editing, but the fact is that my "viewing list" at the bottom of page told me that no one was replying to the thread while I was.

I've set my profile to 'invisible', so no-one can see what I'm doing here

. I've done this because I got a lot of "helpz me pleaaasse!!!11oneone!!" PM's when people saw that I was looking at a thread. I didn't like getting all those PM's begging for help, so I selected 'invisible mode' and it helped quite a bit.