Vector in C

[midnight]

Hello, guys!
I'm a begginner with C. And I wonder if there is Vector in C? Or how could I implement it? Need help. pls.

[laserlight]

What do you mean by "vector"?

[midnight]

Vectors are commonly used instead of arrays, because they expand automatically when new data is added to them.

[cph]

Hello, guys!
I'm a begginner with C. And I wonder if there is Vector in C? Or how could I implement it? Need help. pls.

I don't think so, you implement that by using singly/doubly linked lists

[laserlight]

Vectors are commonly used instead of arrays, because they expand automatically when new data is added to them.

No such functionality is provided by the C standard library. However, you can use the memory management functions available from <stdlib.h> to obtain dynamic array functionality.

[midnight]

yup, I'll try to implement a dynamic array. thx a lot

[midnight]

Do you know how could I get the size of structure? I need to sort values in it... but i dont know how

[laserlight]

You can use the sizeof operator.

[midnight]

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
struct Data {
char *name[50];

} ;

struct Data *the_array = NULL;
int num_elements = 0; // Keeps track of the number of elements used
int num_allocated = 0; // This is essentially how large the array is
int control;
struct Data *tmp;
struct Data *a;
int i;
//void * realloc ( void * ptr, size_t size );

int AddToArray (struct Data item)
{
if(num_elements == num_allocated) // Are more refs required?
{
// Feel free to change the initial number of refs
// and the rate at which refs are allocated.
if (num_allocated == 0)
num_allocated = 0;
else
num_allocated ++;
// Make the reallocation transactional
// by using a temporary variable first
//void *_tmp = realloc(the_array, (num_allocated * sizeof(struct Data)));
tmp = (struct Data*)malloc(num_allocated*(sizeof(struct Data)));
// If the reallocation didn't go so well,
// inform the user and bail out
if (!tmp)
{
fprintf(stderr, "ERROR: Couldn't realloc memory!\n");
return(-1);
}
// Things are looking good so far
the_array = (struct Data*)tmp;
}

the_array[num_elements] = item;
num_elements++;

return num_elements;
}

int main (void)
{


while ((getchar() != 4)){
getwchar(a->name);


}




}

(

[C_ntua]

Or you can use C++ which provide a vector, if you don't necessarily need to use C.
They are almost identical, with some small differences (excluding the OOP stuff of course)

[midnight]

Or you can use C++ which provide a vector, if you don't necessarily need to use C.
They are almost identical, with some small differences (excluding the OOP stuff of course)

I'd like to, but the program must be written in C. I have already it in C++, it works perfectly, but I don't know how it to do in C. This is the problem

[laserlight]

Please post your code in [code][/code] bbcode tags.

Do you really want name to be an array of 50 pointers to char? I suspect that you want it to be either an array of 50 char, or a pointer to char.

[midnight]

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
struct Data	 {
char *name[50];

} ;

struct Data    *the_array = NULL;
int     num_elements = 0; // Keeps track of the number of elements used
int     num_allocated = 0; // This is essentially how large the array is
int control;
struct Data *tmp;
struct Data *a;
int i;
//void * realloc ( void * ptr, size_t size );

int AddToArray (struct Data item)
{
        if(num_elements == num_allocated) // Are more refs required?
        {
                // Feel free to change the initial number of refs
                // and the rate at which refs are allocated.
                if (num_allocated == 0)
                        num_allocated = 0; 
                else
                        num_allocated ++; 
                // Make the reallocation transactional
                // by using a temporary variable first
                //void *_tmp = realloc(the_array, (num_allocated * sizeof(struct Data)));
			 	tmp = (struct Data*)malloc(num_allocated*(sizeof(struct Data)));
                // If the reallocation didn't go so well,
                // inform the user and bail out
                if (!tmp)
                {
                        fprintf(stderr, "ERROR: Couldn't realloc memory!\n");
                        return(-1);
                }
                // Things are looking good so far
                the_array = (struct Data*)tmp;
        }
		
        the_array[num_elements] = item;
        num_elements++;
	
        return num_elements;       
}

int  main (void)
{

	
	while ((getchar() != 4)){	
 		getwchar(a->name);
 	}
 	printf("--------------------------\n");
 	
 
	
}

[laserlight]

Another thing: avoid global variables.

[Elysia]

SourceForge.net: Common mistakes and errors - cpwiki