Linked List

[am_abbas]

Hi Gurus,

I have created a linked list but dosent work. Can any one tell me what is worng, please.

Thanks and Regards,
Abbas

struct mass_list_s
{
double a_v_cg[4];
char *name;
struct mass_list_s *link;
}


add_to_list(struct mass_list_s **q,double av_cg[4],char nm[64])
{
struct mass_list_s *temp;

int i;
char buff[1000];
temp=*q;



if(*q==NULL)
{
*q=malloc(sizeof(struct mass_list_s));
temp=*q;
}

else
{
while(temp->link!=NULL)temp=temp->link;
temp->link=malloc(sizeof(struct mass_list_s));
temp=temp->link;
}

for(i=0;i<4;i++)temp->a_v_cg[i]=av_cg[i];
temp->name=nm;
temp->link=NULL;
}
display_list(struct mass_list_s *q)
{
while(q!=NULL)
{
printf("%l,%l,%l,%l",q->a_v_cg[0],q->a_v_cg[1],q->a_v_cg[2],q->a_v_cg[3]);
q=q->link;
}
}

[KabalProg]

Hi. I would like to know what seems to be the problem, because it seems to work fine. I only did a change:

temp->name=nm;

changed to:

int l = strlen(nm);
temp->name = (char*)malloc(l+1);
strcpy(temp->name, nm);

Also, when you are printing, you can't use %l, because that's for long int, and you have double, so you must use %lf.

The correct way to use it is like this:

mass_list_s *p=NULL;
double a[4]={1.,2.,3.,4.};
double b[4]={4.,5.,6.,7.};
double c[4]={8.,9.,10.,11.};
add_to_list(&p,a,"test#1");
add_to_list(&p,b,"test#2");
add_to_list(&p,c,"test#3");

display_list(p);

I tried it with the following program:

#include <stdio.h>
#include <string.h>
#include <malloc.h>

struct mass_list_s
{
double a_v_cg[4];
char *name;
struct mass_list_s *link;
};


void add_to_list(struct mass_list_s **q,double av_cg[4],char nm[64])
{
struct mass_list_s *temp;

int i;
temp=*q;

if(*q==NULL)
{
*q=(mass_list_s*)malloc(sizeof(struct mass_list_s));
temp=*q;
}

else
{
while(temp->link!=NULL)temp=temp->link;
temp->link=(mass_list_s*)malloc(sizeof(struct mass_list_s));
temp=temp->link;
}

for(i=0;i<4;i++)temp->a_v_cg[i]=av_cg[i];
//temp->name=nm;
int l = strlen(nm);
temp->name = (char*)malloc(l+1);
strcpy(temp->name, nm);
//done
temp->link=NULL;
}

void display_list(struct mass_list_s *q)
{
while(q!=NULL)
{
printf("%lf,%lf,%lf,%lf\n",q->a_v_cg[0],q->a_v_cg[1],q->a_v_cg[2],q->a_v_cg[3]);
q=q->link;
}
}

int main()
{
mass_list_s *p=NULL;
double a[4]={1.,2.,3.,4.};
double b[4]={4.,5.,6.,7.};
double c[4]={8.,9.,10.,11.};
add_to_list(&p,a,"test#1");
add_to_list(&p,b,"test#2");
add_to_list(&p,c,"test#3");

display_list(p);

return 1;
}


Hope this helps,

KabalProg