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having a few problems with my code - output

Yazz398 (1)
Hey all im trying to get my code to work but I get a few errors in the int main
Anyone able to help me?
I believe the root of the problem is in line 150 but I cant seem to fix it.
Thanks

Full code:
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#include <iostream>
#include <string>
#include <fstream>
#include <cstring>
using namespace std;

char instr[81];
FILE *stream;
int getline(char*,int);

//double getline(string*,double);
class Custome {// The class
  int jj;
  
 public:  
 Custome(){ 
      jj = 0.0;
  }
  Custome(int jj){
      this->jj = jj;
}
void set_jj(){
    getline(instr,81);
    jj = atof(instr);
    }
  int get_jj(){return jj;}
  void calc_jj_precent(){
      
  }
  ~Custome(){};
};
  class New : public Custome{
  
  int account;
    char* firstName;  
    char* lastName;  
    double minutes;
    char* length;
   double active;
    char stat[81];
    New(){};
    New(int account, char* firstName, char* lastName, double minutes, char* length, double active, char* stat, int jj, double calc_jj_precent) : Custome(jj){
            this->account=account;
			std::strcpy(this->firstName,firstName);
			this->minutes=minutes;
			std::strcpy(this->length,length);
			this->active=active;
		    std::strcpy(this->stat,stat);
}

		void set_account(){
		   getline(instr,81);}
		 int get_account(){return account;}
		 
		void set_firstName(){
		    getline(firstName,81);}
		 char *get_firstName(){return firstName;}
		 
		 void set_lastName(){
		    getline(lastName,81);}
		 char *get_lastName(){return lastName;}

          void set_minutes(){
		   getline(instr,81);}
		 double get_minutes(){return minutes;}
		
	     void set_length(){
		    getline(length,81);}
		 char *get_length(){return length;}
		 
		  void set_active(){
		   getline(instr,81);}
		 double get_active(){return active;}
		 
 void set_stat(){
		    getline(stat,81);}
		 char *get_stat(){return stat;}
		
	
		
		double calc_jj_precent(){return (get_jj()/100.0);}
		
		
		
		friend istream & operator >> (istream &in, New &New)
	
			{ 
				   
				    New.set_account();
					
					New.set_firstName();
					
					New.set_lastName();

					New.set_minutes();
					
					New.set_length();
					
					New.set_active();
					
					New.set_stat();
					
					New.set_jj();
					
					New.calc_jj_precent();
						
					return in; 
			}//friend	

		
		

	friend ostream &operator<<(ostream &output, New &New){		
		output << "\nAccount "	<<New.get_account();
		output << "\nFirstnamed "		<<New.get_firstName();
		output << "\nLastnamed "		<<New.get_lastName();
		output << "\nMinutes "		<<New.get_minutes();
		output << "\nLength "		<<New.get_length();
		output << "\nActive "		<<New.get_active();
		output << "\nStat "		<<New.get_stat();
		output << "\nJj "		<<New.get_jj()<<endl;
		output << "\nJjPrecent "		<<New.calc_jj_precent()<<endl;
			return output;
		}
		
		void display();
		~New(){};
			
	

};

void New::display(){ 
	cout << "\nAccount: " 		<< account;
	cout << "\nFirstName: " 	<< firstName;
	cout << "\nLastName: "		<< lastName;
cout << "\nMinutes: " 		<< minutes;
	cout << "\nLength: " 			<< length;
	cout << "\nActive: " 			<< active;
	cout << "\nStat: " 		<< stat;
	cout << "\nJj: " 		<< get_jj();
	cout << "\nJjprecent: " << calc_jj_precent()<<endl;
}

int n,num_recs=0;

int main(void) {

// Create an instance of the Player class
New New(New.get_account(),New.get_firstName(),New.get_lastName(),New.get_minutes(),New.get_length(),New.active(),New.get_stat(),New.get_jj(),New.calc_jj_precent());


//Used to create the file initially.

stream = fopen("New.txt","w+b");

for(int i=0;i<3;i++){
	cin >> New;
	
				/*New.set_account();				
				New.set_firstName();
				New.set_lastName();
				New.set_minutes();				
				New.set_length();				
				New.set_active();
				New.set_stat();
				New.set_jj();				
				New.calc_jj_precent();
				*/
	
		//Write to the File

	fseek(stream,i*sizeof(New),0);	
	fwrite(&New,sizeof(New),1,stream);

}
fclose(stream);


stream = fopen("New.txt","r+b");

for(;;){
	   //Read a record
	n = fread(&New,sizeof(New),1,stream);
	if(!n)break;

	cout <<"\nPrinting output from New.Display() function:";
	New.display();
	
	cout <<"\n\nPrinting output from New friend function:";
	cout << New;
	
	num_recs++;
		
	void pause();
	{
		cout << "\n PRESS ANY KEY TO CONTINUE.... \n";
		
		
	}
}

cout << "\n\nThe number of records read from the file was: " << num_recs <<endl;

fclose(stream);

void pause();
{
	cout << "\n PRESS ANY KEY TO CONTINUE.... \n";
	
	
}

}//main










line150
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2
 
 
New New(New.get_account(),New.get_firstName(),New.get_lastName(),New.get_minutes(),New.get_length(),New.active(),New.get_stat(),New.get_jj(),New.calc_jj_precent());


line158
cin >> New;

line173
fseek(stream,i*sizeof(New),0);

line174
fwrite(&New,sizeof(New),1,stream);

line184
n = fread(&New,sizeof(New),1,stream);

line188
New.display();
Last edited on
salem c (3700)
OK, some things.

1. Pick an indent style and stick to it -> https://en.wikipedia.org/wiki/Indentation_style
In particular, don't mix spaces and tabs. Your editor might cope, but sooner or later, some other editor or forum post will make a steaming pile out of it.
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#include <iostream>
#include <string>
#include <fstream>
#include <cstring>
using namespace std;

char instr[81];
FILE *stream;
int getline(char *, int);

//double getline(string*,double);
class Custome {                 // The class
  int jj;

public:
  Custome() {
    jj = 0.0;
  }
  Custome(int jj) {
    this->jj = jj;
  }
  void set_jj() {
    getline(instr, 81);
    jj = atof(instr);
  }
  int get_jj() {
    return jj;
  }
  void calc_jj_precent() {
  }
  ~Custome() {
  };
};

class New:public Custome {
  int account;
  char *firstName;
  char *lastName;
  double minutes;
  char *length;
  double active;
  char stat[81];
  New() {
  };
  New(int account, char *firstName, char *lastName, double minutes, char *length, double active, char *stat, int jj,
      double calc_jj_precent):Custome(jj) {
    this->account = account;
    std::strcpy(this->firstName, firstName);
    this->minutes = minutes;
    std::strcpy(this->length, length);
    this->active = active;
    std::strcpy(this->stat, stat);
  }
  void set_account() {
    getline(instr, 81);
  }
  int get_account() {
    return account;
  }
  void set_firstName() {
    getline(firstName, 81);
  }
  char *get_firstName() {
    return firstName;
  }
  void set_lastName() {
    getline(lastName, 81);
  }
  char *get_lastName() {
    return lastName;
  }
  void set_minutes() {
    getline(instr, 81);
  }
  double get_minutes() {
    return minutes;
  }
  void set_length() {
    getline(length, 81);
  }
  char *get_length() {
    return length;
  }
  void set_active() {
    getline(instr, 81);
  }
  double get_active() {
    return active;
  }
  void set_stat() {
    getline(stat, 81);
  }
  char *get_stat() {
    return stat;
  }
  double calc_jj_precent() {
    return (get_jj() / 100.0);
  }
  friend istream & operator >>(istream & in, New & New)
  {
    New.set_account();
    New.set_firstName();
    New.set_lastName();
    New.set_minutes();
    New.set_length();
    New.set_active();
    New.set_stat();
    New.set_jj();
    New.calc_jj_precent();
    return in;
  }                             //friend
  friend ostream & operator<<(ostream & output, New & New) {
    output << "\nAccount " << New.get_account();
    output << "\nFirstnamed " << New.get_firstName();
    output << "\nLastnamed " << New.get_lastName();
    output << "\nMinutes " << New.get_minutes();
    output << "\nLength " << New.get_length();
    output << "\nActive " << New.get_active();
    output << "\nStat " << New.get_stat();
    output << "\nJj " << New.get_jj() << endl;
    output << "\nJjPrecent " << New.calc_jj_precent() << endl;
    return output;
  }

  void display();

  ~New() {
  };
};

void New::display()
{
  cout << "\nAccount: " << account;
  cout << "\nFirstName: " << firstName;
  cout << "\nLastName: " << lastName;
  cout << "\nMinutes: " << minutes;
  cout << "\nLength: " << length;
  cout << "\nActive: " << active;
  cout << "\nStat: " << stat;
  cout << "\nJj: " << get_jj();
  cout << "\nJjprecent: " << calc_jj_precent() << endl;
}

int n, num_recs = 0;

int main(void)
{
  // Create an instance of the Player class
  New New(New.get_account(), New.get_firstName(), New.get_lastName(), New.get_minutes(), New.get_length(), New.active(),
          New.get_stat(), New.get_jj(), New.calc_jj_precent());

  //Used to create the file initially.
  stream = fopen("New.txt", "w+b");
  for (int i = 0; i < 3; i++) {
    cin >> New;
    /*New.set_account();
       New.set_firstName();
       New.set_lastName();
       New.set_minutes();
       New.set_length();
       New.set_active();
       New.set_stat();
       New.set_jj();
       New.calc_jj_precent();
     */
    //Write to the File
    fseek(stream, i * sizeof(New), 0);
    fwrite(&New, sizeof(New), 1, stream);
  }
  fclose(stream);

  stream = fopen("New.txt", "r+b");
  for (;;) {
    //Read a record
    n = fread(&New, sizeof(New), 1, stream);
    if (!n)
      break;

    cout << "\nPrinting output from New.Display() function:";
    New.display();
    cout << "\n\nPrinting output from New friend function:";
    cout << New;
    num_recs++;
    void pause();
    {
      cout << "\n PRESS ANY KEY TO CONTINUE.... \n";
    }
  }

  cout << "\n\nThe number of records read from the file was: " << num_recs << endl;

  fclose(stream);

  void pause();
  {
    cout << "\n PRESS ANY KEY TO CONTINUE.... \n";
  }

}                               //main


> char instr[81];
> FILE *stream;
> int getline(char *, int);
1. Avoid global variables.
2. This is C++, so why are you using a C-style FILE* stream
3. Don't re-prototype standard methods -> https://www.cplusplus.com/reference/istream/istream/getline/

> std::strcpy(this->firstName, firstName);
You don't allocate any memory to copy into.

Replace ALL your char* with std::string, and get something that works without the need for all this micro-management of memory.

Also, you should have prototyped this whole 'New' class with just a couple of members and methods, before massively copy/pasting yourself into a much deeper hole.

> New New(New.get_account(), New.get_firstName(), New.get_lastName(), New.get_minutes(), New.get_length(), New.active(),
> New.get_stat(), New.get_jj(), New.calc_jj_precent());
This is strangely incestuous. How can you call your constructed 'get' methods at the start of your constructor?

> fwrite(&New, sizeof(New), 1, stream);
No, and No.
Your first 'No' is that your class contains pointers. It's not going to magically dereference those pointers for you.
Your second 'No' is that you already overload the << and >> operators.
You should use these to output and input instances of your class.



Last edited on
seeplus (6592)
As you are using fixed size record file binary read/write for the classes (fseek, fwrite etc), the classes cannot contain any dynamic memory or pointers to memory (ie no string, vector , char* etc). You should only use arrays of basic types (int, double, char etc).

If you want to use say string as a type for a variable in a class (recommended), then you need to read/write the file as text sequentially but you cannot easily read an individual record. In this case it would be usual for the whole file to be read into say a vector of class first and then used as appropriate.

You need to decide which file method you are going to use - or has this been specified as part of the program spec. You can't mix.



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