Thread: Same Questiion But I Do Not Know How To Do It In Linked List.

here is the same progrm just more efficient(works fine).please explain where and how to modify it to linked lists.

Code:

#include<stdio.h>
#include<string.h>
#include<stdlib.h>
        /**************************************************************/
                /*Declaration of a Structure of Type PART*/ 
typedef struct {
        int    ID;
        char   desc[50];
        int    quant;
        float  price;
        
        }PART;
        /*************************************************************/
PART part[1000];
int count=0;
int parts_sold=0;
float total=0;
FILE*in;
/******************************************************************************/
                        /*Declaration of Functions*/
void insertinorder(int);
void getdescription(char[]); 
void addnewpart();
void changeprice();
void addquant();
void sellpart();
void printparts();
int  binarysearch(int);
/******************************************************************************/
/*
   The Main Function Opens the file "parts.dat" and reads the required data
   And assigns the data to the Structure based on its Field.
   It Then Calls The Various Funtions Based On The "Code" Received.
*/

int main () 
{    
    int tempid,execute=1;
    char word[100],ch;
    char chs[3];    
    
    in=fopen("parts.dat","r");
    if (in==NULL){
                  printf("Error!!!File \"parts.dat\" Not Found\n");
                  system("pause");
                  return 1;
                 } 
    
    fscanf(in,"&#37;d",&tempid);
    while(tempid!=0)
         {
                insertinorder(tempid);
                count++;
                fscanf(in,"%d",&tempid);
         }      
            
      while (execute==1)      
    {                     
        ch=getc(in);
        while (ch == ' ') 
              ch=getc(in);
              
        chs[0]=getc(in);
        
        if (chs[0] != EOF) 
        {
           chs[1]=getc(in);
           chs[2]='\0';
           
           if (strcmp(chs,"ap")==0)
               addnewpart();
        
      else if (strcmp(chs,"sp")==0)          
               sellpart();   
               
      else if (strcmp(chs,"cp")==0)          
               changeprice();    
    
      else if (strcmp(chs,"cq")==0)           
               addquant();
               
      else if (strcmp(chs,"ls")==0)            
               printparts();
        }
      else
          execute=0;   
    } 
         
     printf("\nThe Total Number Of Parts Sold Was:%d\n",parts_sold);
     printf("The Total Sales Amounted to:$%5.2f\n",total);
         
             printf("\n");
             fclose(in);
             system("pause");
             return 0;
             
}
/******************************************************************************/
/*
    The Following Function Is Responsible For Inserting A Part In Order.
*/
void insertinorder(int tempid)
{
     int k=count-1;
     while (k>=0 && tempid<part[k].ID){
           part[k+1]=part[k];
           k--;
           }
     part[k+1].ID=tempid;
     getdescription(part[k+1].desc);
     fscanf(in,"%d",&part[k+1].quant);
     fscanf(in,"%f",&part[k+1].price);
}     
/******************************************************************************/
/*
    The Following Function Is Responsible For Capturing The Description
    Whilst Rejecting The Character "*" Between Which The Description Is 
    Encased.
*/
void getdescription(char word[])
{
     char c;
     int n=0;
     
     while ((c=getc(in))== ' ' && c!='*') ;
     c=getc(in);
     word[n]=c;
     
     while ((c=getc(in))!='*') 
     {
           n++;
           word[n]=c;
     }
     word[++n]='\0';
}     

/******************************************************************************/
/*
    The Following Function Adds A New Part To The List Of Existing Parts
    In Order.
*/
void addnewpart()
{
     int tempid;
     fscanf(in,"%d",&tempid);
     insertinorder(tempid);
     count++;
}
/*****************************************************************************/
/*  
  The Following Function Updates The Price Field Of A Part
*/
void changeprice()
{
     int id,ID;
     float newprice;
     fscanf(in,"%d",&id);
     fscanf(in,"%f",&newprice);
     ID=binarysearch(id);
        if (ID==-1)
        printf("\nThe Part %d Price Cannot Be Altered. Part Entry Not Found!\n",id);
     else  
        {
         part[ID].price=newprice;    
        }
}
/*****************************************************************************/
/*  
    The Following Function Updates The Quantity Field Of 
    A Part(Adds To The Quantity.)
*/
void addquant()
{
     int id,ID,quant;
     fscanf(in,"%d",&id);
     fscanf(in,"%d",&quant);
     ID=binarysearch(id);
        if (ID==-1)
        printf("\nThe Part %d Quantity Cannot be Added. Part Entry Not Found!\n",id);
     else  
        {
         part[ID].quant=part[ID].quant+quant;
        }
}
/*****************************************************************************/
/*  
    The Following Function Checks If There Is Sufficient 
    Quantity Of A Part To Sell, Then Modifies The Quantity
    After Subtracting The Amount To Be Sold.
*/
void sellpart()
{     
     int id,ID,quant;
     fscanf(in,"%d",&id);
     fscanf(in,"%d",&quant);
     ID=binarysearch(id);
        if (ID==-1)
        printf("\nThe Part %d Cannot Be Sold. Part Entry Not Found!\n",id);
     else  
        {
          
          if(part[ID].quant<quant)
             printf("\nThe Part %d Cannot be Sold.Not Enough Stock!\n",id);
          else
          {              
             part[ID].quant=part[ID].quant-quant; 
             parts_sold=parts_sold+quant;
             total=total+(part[ID].price * quant);
          }   
        }  
}
/*****************************************************************************/
/*  
    When Called, This Function Prints The Entire List Of Parts
    Along With The Respective Description,Price And Quantity. 
*/
void printparts()
{
     int i;
    
     printf("\nPart ID.\tDescription\t\tCurrent Quantity\tPrice\n\n");
     for (i=0; i<count; i++)
     printf("%d\t\t%-30s\t%d\t\t%5.2f\n",part[i].ID, part[i].desc, part[i].quant, part[i].price);
      
}
/*****************************************************************************/
/*  
    This Function Searches For A Given Key.It Returns The Location Of 
    The Key If Found and -1 If It Isn't Found.
*/
int binarysearch(int id)
{    
     int mid,lo=0,hi=count;
     while(lo<=hi)
     {
       mid=(lo+hi)/2;
             if(part[mid].ID==id)
             return mid;
        else if(id<part[mid].ID)
             hi=mid-1;
        else
             lo=mid+1;                   
     } 
     return -1;
}
/*****************************************************************************/

honestly i dont!that's why im just lost and most likely asking stupid questions.all i wanted to know is how do i convert this code that i posted into linked list. it was tough enouh for me to write the program with just structures .Plus u said i had redundant code so i thought i'd fix that one time.my bad. i really would appreciate it if you would explain to me what needs to be done here. i understand the layout of the linked list and how to make new nodes for it but i cant use it.

YES it does i got somewhere to start now.ill check you guys back when i reach somewhere with this.thanks DWK

okay i wrote over the insertion sort but i dont think it reads anything.it prints eeverything but the figures are all 0's
can you tell me where my error is?
i make a cll in the while statement top= insertinorder(top,tempid);
tempid was declared as an int.

Code:

ptr insertinorder(ptr top,int tempid){
ptr np,curr,prev,makenode(int);
  np=makenode(tempid);
prev=NULL;
curr=top;
while(curr!=NULL && tempid>curr->num){
prev=curr;
curr=curr->next;
}
if(prev==NULL){
                        np->next=top;
return np;}
np->next=curr;
prev->next=np;
return top;
}

okay i give up.this too hard for me il stick to math alone.depressing!