how do I find the length of and array using sizeof()

Damm I forgot this I knew this a week ago but it slipped out.

Code:

---


#include<stdio.h>

main()
{
      int x;
      char array[100][50] =
      {
            {"element 1"},
            {"element 2"},
            {"element 3"},
            {"element 4"}
      };
       
      x = sizeof(array)/sizeof(array[0]);
      printf("the size of the array is %d",x);
      getchar();
}

---

I am not getting the right results it should be 4 not 100 I forgot this I knew this a week ago. I guess the old saying is true in programming if you don't use it you lose it

It shouldn't be 4. You have declared a 100 x 50 array, it has all those elements, you have only initialized a few of them. The rest initialize to zero.


Quzah.

is there a short cut notation in c to initialize the rest of the elements to the null character?

Thanks for the reply by the way I really appreciate it

If you initialize any elements of an array, all uninitialized elements are initialized to zero by default.


Quzah.

char array[100] = {0};

you use this short hand notation to explicitly set the first element to zero and implicitly set all the other elements to zero
when you first initialize an array


I just had to get that into in my head

Code:

---


    int i;
 
      char array[100] = {0}; // explicitly set the first element to zero and implicitly set all the other elements to zero

      array[0] = 1;
      array[1] = 2;
     
      for(i =0; array[i] != 0; i++)
      {
      }     
     
      printf("the size of the array is %i",i);

---

thanks all later gents I like this forum by the way.

This does only work if the actual content of an array element isn't 0, which is absolutely possible.

As KONI said, That's not going to give you the size of the array...

I dont really think that there is any other way of finding a length other than traversing the array through a loop.

May be any one have better idea?

ssharish2005

It doesn't look like they really want the array's size. It looks like they just want to know how many in a row from the start aren't zero filled.

Quzah.

I suppose you could have a struct where you would have a pointer, representing your array and a regular int to hold the size. There are other variations on this. Of course, the important thing is to make sure that the size variable is altered everytime the size of the array changes.