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Join Date: Apr 2008

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Reputation: christiangirl is an unknown quantity at this point

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christiangirl christiangirl is offline

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Junior Poster

linked list

Dec 8th, 2008

Hey,
I am having problems with this code, I think it is not linking up the whole file, because when I run it it only says "hi" 3 times. And also it keeps crashing because of best[i] = point->item->return_value();

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
#include "applicant.cpp"
#include <iostream>
#include <fstream>
#include <iomanip>
 
using namespace std;
 
struct Employeelink
{
 int id;
 int yearsWorked;
 char skillLevel;
 Applicant *item;
 Employeelink *next;
 
};
 
class Promosion
{
      protected:
         float value;
         Employeelink *start;
         Employeelink *lastone;
      public:
         Promosion(void); 
         void linkup(Employeelink);
         int best(void);       
};
 
Promosion::Promosion()
{
   //start = NULL;
   lastone = NULL;                  
}
 
void
Promosion::linkup(Employeelink employee)
{
   Employeelink *another;
   another = new Employeelink;
   another->id = employee.id;
   another->skillLevel = employee.skillLevel;
   another->yearsWorked = employee.yearsWorked;
 
   lastone = another;
   //start = another;
}
 
int
Promosion::best()
{
  float value[18];
  Employeelink *point;
  float best[18];
  point = start;
  int i = 0;
  float totalBest;
  //point = point->next;
  while(point != NULL)
  {
              cout << "hi" << endl;
    best[i] = point->item->return_value();
    point = point->next;
    i++;
  }
  for(int x = 0; x < i; x++)
  {
    for(int y = 0; y < i; y++)
    {
         if(best[x] > best[y])
            totalBest = best[x];
 
    }
  }
}
 
int
main()
{
 ifstream partin;
 Employeelink emp, temp;
 Promosion applicant;
 
 partin.open("applicnt.dat");  
 if(partin.fail())
 {
    cout << "Error: Unable to open file!" << endl;  
    partin.clear();
 }
 
 partin >> temp.id;
 while(!partin.eof())
 {
    emp.id  = temp.id;      
    partin >> emp.skillLevel;
    partin >> emp.yearsWorked;
    applicant.linkup(emp);    
 }
 
 applicant.best();
 
 system("pause");
 return EXIT_SUCCESS;
}
#include "applicant.cpp"
#include <iostream>
#include <fstream>
#include <iomanip>

using namespace std;

struct Employeelink
{
 int id;
 int yearsWorked;
 char skillLevel;
 Applicant *item;
 Employeelink *next;
 
};

class Promosion
{
      protected:
         float value;
         Employeelink *start;
         Employeelink *lastone;
      public:
         Promosion(void); 
         void linkup(Employeelink);
         int best(void);       
};

Promosion::Promosion()
{
   //start = NULL;
   lastone = NULL;                  
}

void
Promosion::linkup(Employeelink employee)
{
   Employeelink *another;
   another = new Employeelink;
   another->id = employee.id;
   another->skillLevel = employee.skillLevel;
   another->yearsWorked = employee.yearsWorked;
  
   lastone = another;
   //start = another;
}

int
Promosion::best()
{
  float value[18];
  Employeelink *point;
  float best[18];
  point = start;
  int i = 0;
  float totalBest;
  //point = point->next;
  while(point != NULL)
  {
              cout << "hi" << endl;
    best[i] = point->item->return_value();
    point = point->next;
    i++;
  }
  for(int x = 0; x < i; x++)
  {
    for(int y = 0; y < i; y++)
    {
         if(best[x] > best[y])
            totalBest = best[x];
            
    }
  }
}

int
main()
{
 ifstream partin;
 Employeelink emp, temp;
 Promosion applicant;
 
 partin.open("applicnt.dat");  
 if(partin.fail())
 {
    cout << "Error: Unable to open file!" << endl;  
    partin.clear();
 }
 
 partin >> temp.id;
 while(!partin.eof())
 {
    emp.id  = temp.id;      
    partin >> emp.skillLevel;
    partin >> emp.yearsWorked;
    applicant.linkup(emp);    
 }
 
 applicant.best();
             
 system("pause");
 return EXIT_SUCCESS;
}

here is the class it calls:

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
 
/*----------------------------------------------------------------
   this file includes the class Applicant and a constant of 3.4
   used to calculate an applicant's value
   filename: applicant.cpp
----------------------------------------------------------------*/
 
#include <iostream>
 
using namespace std;
 
const float indexnumber = 3.4;
 
class Applicant
{
  protected:
    int   id;
    char  skill;
    int   years;
    float value;
  public:
    Applicant(void);
    void  store_id(int);
    void  store_skill(char);
    void  store_years(int);
    void  calc_value(void);
    int   return_id(void);
    char  return_skill(void);
    int   return_years(void);
    float return_value(void);
};
 
Applicant::Applicant()
{
  id = 0;
  skill = '@';
  years = 0;
  value = -1;
}
 
void
Applicant::store_id(int who)
{
  id = who;
}
 
void
Applicant::store_skill(char level)
{
  skill = level;
}
 
void
Applicant::store_years(int howlong)
{
  years = howlong;
}
 
void
Applicant::calc_value()
{
  float skillvalue, yearsvalue;
 
  switch(skill)
  {
    case 'D': skillvalue = indexnumber;
              break;
    case 'C': skillvalue = 1.3 * indexnumber;
              break;
    case 'B': skillvalue = 1.7 * indexnumber;
              break;
    case 'A': skillvalue = 2.1 * indexnumber;
              break;
    default:  skillvalue = 0;
  }
 
  if (years <= 5)
    yearsvalue = years;
  else
    yearsvalue = 5 + (years - 5) * 0.5;
 
  value = skillvalue + yearsvalue;
}
 
int
Applicant::return_id()
{
  return id;
}
 
char
Applicant::return_skill()
{
  return skill;
}
 
int
Applicant::return_years()
{
  return years;
}
 
float
Applicant::return_value()
{
  if (value == -1)
    calc_value();
  return value;
}
                                             
/*----------------------------------------------------------------
   this file includes the class Applicant and a constant of 3.4
   used to calculate an applicant's value
   filename: applicant.cpp
----------------------------------------------------------------*/

#include <iostream>

using namespace std;

const float indexnumber = 3.4;

class Applicant
{
  protected:
    int   id;
    char  skill;
    int   years;
    float value;
  public:
    Applicant(void);
    void  store_id(int);
    void  store_skill(char);
    void  store_years(int);
    void  calc_value(void);
    int   return_id(void);
    char  return_skill(void);
    int   return_years(void);
    float return_value(void);
};

Applicant::Applicant()
{
  id = 0;
  skill = '@';
  years = 0;
  value = -1;
}

void
Applicant::store_id(int who)
{
  id = who;
}

void
Applicant::store_skill(char level)
{
  skill = level;
}

void
Applicant::store_years(int howlong)
{
  years = howlong;
}

void
Applicant::calc_value()
{
  float skillvalue, yearsvalue;
  
  switch(skill)
  {
    case 'D': skillvalue = indexnumber;
              break;
    case 'C': skillvalue = 1.3 * indexnumber;
              break;
    case 'B': skillvalue = 1.7 * indexnumber;
              break;
    case 'A': skillvalue = 2.1 * indexnumber;
              break;
    default:  skillvalue = 0;
  }
  
  if (years <= 5)
    yearsvalue = years;
  else
    yearsvalue = 5 + (years - 5) * 0.5;
    
  value = skillvalue + yearsvalue;
}
  
int
Applicant::return_id()
{
  return id;
}

char
Applicant::return_skill()
{
  return skill;
}

int
Applicant::return_years()
{
  return years;
}

float
Applicant::return_value()
{
  if (value == -1)
    calc_value();
  return value;
}

And here is the data in the file it reads:
14101 A 6
11100 C 2
20056 D 10
15594 D 8
23231 B 12
16649 A 5
22334 B 13
19876 C 10
22435 A 9
14231 B 8
16767 C 5
17890 D 11
19045 C 16
10001 A 4
20341 B 7
14578 C 23
20011 D 20
15560 B 10

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Join Date: Aug 2005

Posts: 15,397

Reputation: Ancient Dragon has a reputation beyond repute

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Ancient Dragon Ancient Dragon is offline

Offline

Still Learning

Re: linked list

Dec 8th, 2008

>>#include "applicant.cpp"
Never, ever, under NO circumstances, do this!! DO NOT INCLUDE *.CPP like that. Instead, compile them separately and link the object modules. How to do that depends on the compiler you are using.

Don't PM me with questions -- you might get a nasty PM in response. If you have a question then post it in one of the forums.

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Join Date: Apr 2008

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Reputation: christiangirl is an unknown quantity at this point

Solved Threads: 1

christiangirl christiangirl is offline

Offline

Junior Poster

Re: linked list

Dec 8th, 2008

ok.
I changed the code a little, but at the couts I am getting weird numbers that are not in the file applicnt.dat as well as the numbers that are
here is the new code

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
#include "applicant.cpp"
#include <iostream>
#include <fstream>
#include <iomanip>
 
using namespace std;
 
struct Employeelink
{
 int id;
 int yearsWorked;
 char skillLevel;
 Applicant *item;
 Employeelink *next, *before;
 
};
 
class Promosion
{
      protected:
         float value;
         Employeelink *start;
         Employeelink *lastone;
      public:
         Promosion(void); 
         void linkup(Employeelink);
         int best(void);       
};
 
Promosion::Promosion()
{
   start = NULL;
   lastone = NULL;                  
}
 
void
Promosion::linkup(Employeelink applicant)
{
   Employeelink *another, *last, *here;
   another = new Employeelink;
 
   another->id = applicant.id;
   //cout << another->id << endl;
   another->skillLevel = applicant.skillLevel;
   //cout << another->skillLevel << endl;
   another->yearsWorked = applicant.yearsWorked;
   another->next = lastone;
 
  // lastone = another;
   if(start == NULL)
   {
     start = another;
     start->before = NULL;
   }
   else
   {
       here = start;
   }
   //start = another;
}
 
int
Promosion::best()
{
  float value[18];
  float best[18];
  //point = start;
  int i = 0;
  float totalBest;
 
  Employeelink *point = start;
  while(point != NULL)
  {
    //point->item->return_value();
    //cout << "hi" << endl;
     best[i] = point->item->return_value();
    //cout << "Hi" << i << endl;
    point = point->next;
    i++;
  }
  //cout << i;
  for(int x = 0; x < i; x++)
  {
    for(int y = 0; y < i; y++)
    {
         if(best[x] > best[y])
            totalBest = best[x];
 
    }
  }
}
 
int
main()
{
 int x = 0;
 ifstream partin;
 Employeelink emp, temp;
 Promosion applicant;
 Applicant *app;
 
 partin.open("applicnt.dat");  
 if(partin.fail())
 {
    cout << "Error: Unable to open file!" << endl;  
    partin.clear();
 }
 
 partin >> temp.id;
 while(x < 18)
 {
   x++;
   //cout << x << endl;
    emp.id = temp.id;
   // partin >> emp->id;
    partin >> emp.skillLevel;
    //cout << emp->skillLevel << endl;
    partin >> emp.yearsWorked;
    cout << emp.yearsWorked << endl;
    //app->store_id(emp.id);
    //cout << app->return_id();
    //app->store_years(emp.yearsWorked);
    //app->store_skill(emp.skillLevel);
    applicant.linkup(emp);    
 }
 //cout << x;
 
 applicant.best();
 
 system("pause");
 return EXIT_SUCCESS;
}
#include "applicant.cpp"
#include <iostream>
#include <fstream>
#include <iomanip>

using namespace std;

struct Employeelink
{
 int id;
 int yearsWorked;
 char skillLevel;
 Applicant *item;
 Employeelink *next, *before;
 
};

class Promosion
{
      protected:
         float value;
         Employeelink *start;
         Employeelink *lastone;
      public:
         Promosion(void); 
         void linkup(Employeelink);
         int best(void);       
};

Promosion::Promosion()
{
   start = NULL;
   lastone = NULL;                  
}

void
Promosion::linkup(Employeelink applicant)
{
   Employeelink *another, *last, *here;
   another = new Employeelink;
   
   another->id = applicant.id;
   //cout << another->id << endl;
   another->skillLevel = applicant.skillLevel;
   //cout << another->skillLevel << endl;
   another->yearsWorked = applicant.yearsWorked;
   another->next = lastone;
  
  // lastone = another;
   if(start == NULL)
   {
     start = another;
     start->before = NULL;
   }
   else
   {
       here = start;
   }
   //start = another;
}

int
Promosion::best()
{
  float value[18];
  float best[18];
  //point = start;
  int i = 0;
  float totalBest;
  
  Employeelink *point = start;
  while(point != NULL)
  {
    //point->item->return_value();
    //cout << "hi" << endl;
     best[i] = point->item->return_value();
    //cout << "Hi" << i << endl;
    point = point->next;
    i++;
  }
  //cout << i;
  for(int x = 0; x < i; x++)
  {
    for(int y = 0; y < i; y++)
    {
         if(best[x] > best[y])
            totalBest = best[x];
            
    }
  }
}

int
main()
{
 int x = 0;
 ifstream partin;
 Employeelink emp, temp;
 Promosion applicant;
 Applicant *app;
 
 partin.open("applicnt.dat");  
 if(partin.fail())
 {
    cout << "Error: Unable to open file!" << endl;  
    partin.clear();
 }
 
 partin >> temp.id;
 while(x < 18)
 {
   x++;
   //cout << x << endl;
    emp.id = temp.id;
   // partin >> emp->id;
    partin >> emp.skillLevel;
    //cout << emp->skillLevel << endl;
    partin >> emp.yearsWorked;
    cout << emp.yearsWorked << endl;
    //app->store_id(emp.id);
    //cout << app->return_id();
    //app->store_years(emp.yearsWorked);
    //app->store_skill(emp.skillLevel);
    applicant.linkup(emp);    
 }
 //cout << x;
 
 applicant.best();
             
 system("pause");
 return EXIT_SUCCESS;
}

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Join Date: Aug 2005

Posts: 15,397

Reputation: Ancient Dragon has a reputation beyond repute

Solved Threads: 1466

Ancient Dragon Ancient Dragon is offline

Offline

Still Learning

Re: linked list

Dec 8th, 2008

The while loop is incorrect

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
while( partin >> emp.id >> emp.skillLevel >> emp.yearsWorked)
{
    applicant.linkup(emp);
}
while( partin >> emp.id >> emp.skillLevel >> emp.yearsWorked)
{
    applicant.linkup(emp);
}

Don't PM me with questions -- you might get a nasty PM in response. If you have a question then post it in one of the forums.

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Join Date: Apr 2008

Posts: 108

Reputation: christiangirl is an unknown quantity at this point

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christiangirl christiangirl is offline

Offline

Junior Poster

Re: linked list

Dec 9th, 2008

that makes sense! Its always a simple solution lol.
Thank you very much!

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Join Date: Dec 2007

Posts: 443

Reputation: Agni is a jewel in the rough

Solved Threads: 68

Agni

Online

Posting Pro in Training

Re: linked list

Dec 9th, 2008

Help with Code Tags

C++ Syntax (Toggle Plain Text)

point->item->return_value();

should give a segementation fault.

i saw you 'Promosion::linkup' function and nowhere you are assigning anything to the 'Applicant *item;'. it will be NULL or may be garbage when you access it.

2>system("pause"); is not a good way to do this, you can find a lot of threads here that tell you in detail why. use cin.get() instead.

2>divide applicant.cpp into applicant.h and applicant.cpp and include "applicant.h" and link applicant.cpp

Last edited by Agni; Dec 9th, 2008 at 12:26 am.

thanks
-chandra