Copying text file to struct array

[alex067]

The textfile looks liket his:

Martin Smith/ 22 2.2
Austin Clinton/ 18 3.1
Johnson/ 19 2.9
Maggie Jones/ 23 2.3
Tyler W Brown/16 3.4

I have to copy the data into a struct array of:

const int N = 5;

struct RECORD
{
	char Name[15];
	int Age;
	float Gpa;
};

RECORD p[N]; float GpaAve;

When I try and copy the data and display all of the data, it only displays the first line of the text file data, how do I fix this?

#include <iostream>
#include <array>
#include <fstream>
#include <cstring>


using namespace std;

void CopyRecords(string Fname);
void Display();
void Toupper();

const int N = 5;

struct RECORD
{
	char Name[15];
	int Age;
	float Gpa;
};

RECORD p[N]; float GpaAve;

int main()
{


	// Copy data from file to structure array p 
	CopyRecords("data2.txt");
	
	// Display uppercase 
	Display();

	// Make Name variable all uppercase
	Toupper();




	system("PAUSE");
	return 0;
}

void CopyRecords(string Fname)
{


	fstream f;
	f.open(Fname, ios::in);

	for (int i = 0; i < N; i++)
	{

		f.getline(p[i].Name, 15, '/');
		f >> p[i].Age >> p[i].Gpa;
	}

	f.close();
}


void Display()
{
	
	
	for (int i = 0; i < N; i++)
	{
		cout << p[i].Name << " " << p[i].Age << "/" << p[i].Gpa;
	}
	cout << endl;
	
	// Have all data under variable Name uppercase 
	

}

void Toupper()
{
	
	for (int i = 0; i < N; i++)
	{
		 _strupr(p[i].Name);
	}
	
	
	//Display the data all uppercase
	Display();
}

[anup30]

char Name[15]; > its for max 14 char

use a loop , untill find "/" input then in name
then input age
then gpa

[alex067]

Sorry but I do not understand what you are saying

I cannot INPUT anything, I have to read the data from the file not input my own data...

[anup30]

use vector to store each new line.

if you dont know vector, use pointers > count how many lines are there. and
RECORD rc = new RECORD [totallines];

[alex067]

I cannot use vectors nor can I use pointers.

Let me rephrase my question...

Is there something wrong in this function? Does this not gather all the data from the text file?

void CopyRecords(string Fname)
{


	fstream f;
	f.open(Fname, ios::in);

	for (int i = 0; i < N; i++)
	{

		f.getline(p[i].Name, 15, '/');
		f >> p[i].Age >> p[i].Gpa;
	}

	f.close();
}

Is there something wrong in this function? Does this display all of the information stored from the structure?

void Display()
{
	
	
	for (int i = 0; i < N; i++)
	{
		cout << p[i].Name << " " << p[i].Age << "/" << p[i].Gpa;
	}
	cout << endl;
	
	// Have all data under variable Name uppercase 
	

}

[anup30]

you want to copy data from text file to a structure. for this you have to create structure objets. how many objects? equal to lines of file (==names)

if name numbers are fixed,
you can, RECORD rec[nameNumber];

but if its variable you have to use pointers or vector.

I cannot INPUT anything

i mean input from file, to your program.

[alex067]

Ok can you answer my previous question

[anup30]

why don't you test yourself like this:

#include <iostream>
#include <fstream>
using namespace std;

const int N = 5;

struct RECORD
{
	char Name[15];
	int Age;
	float Gpa;
};

RECORD p[N]; 
float GpaAve;


int main ()
{

	ifstream f;
	in.open("fileName.txt");
	
	for (int i = 0; i < 5; i++)
	{
		f.getline(p[i].Name, 15, '/'); 
		f >> p[i].Age >> p[i].Gpa;
	}
	
	for (int i = 0; i < 5; i++)
	{
	cout << "name " << p[i].Name << " age " <<p[i].Age << " gpa " << p[i].Gpa << endl; // does it show the desired?
	}	
	
	
return 0;	
}

[alex067]

what is the difference between ifstream f; and fstream f;

and why in.open?

text file:
5
22 2.2 Bill Clinton
33 3.3 Phil Jackson
44 4.0 Mary A Johnson
25 2.5 Adam Smith
65 3.2 George W Bush

#include <iostream>
#include <fstream>
#include <array>

using namespace std;

struct PERSON
{
	int age;
	float gpa;
	char name[20];
};
PERSON *p;

void ArraySize(string Fname, int &x);
void CopyData(string Fname, int x);
void DisplayData(int x);

int main()
{
	int size;
	
	ArraySize("two.txt", size); //determine dnynamic array size
	
	cout << "The size of the array is " << size << endl;

	CopyData("two.txt", size); //copy data from file to array p

	DisplayData(size); //Display the data

	system("PAUSE");
	return 0;


}

void ArraySize(string Fname, int  &x)
{
	int n;
	fstream f;
	f.open(Fname, ios::in);
	f >> n;

	x = n;

	f.close();

}

void CopyData(string Fname, int x)
{
	ifstream f;
	f.open(Fname, ios::in);

	for (int i = 0; i < x; i++)
	{
		f >> p[i].age; 
		f >> p[i].gpa;
		f.getline(p[i].name, 20, '\n');
	}

	f.close();
}

void DisplayData(int x)
{
	for (int i = 0; i < x; i++)
	{
		cout << p[i].age << " " << p[i].gpa << " " << p[i].name << endl;
	}
}

Why doesn't this work?

A window pops up saying: "Unhandled exception at x61D735BA (msvcp120d.dll) in Project7(2).exe: 0xC0000005: Access violation writing location 0x00000000.

[anup30]

this worked fine in my pc
inf.txt:

5
22 2.2 Bill Clinton
33 3.3 Phil Jackson
44 4.0 Mary A Johnson
25 2.5 Adam Smith
65 3.2 George W Bush

#include <iostream>
#include <fstream>
using namespace std;

struct PERSON
{
	char Name[50];
	int Age;
	float Gpa;
};
 
float GpaAve;


int main ()
{
	PERSON *ptr;
	int lines;

	ifstream f("inf.txt");
	f >> lines;
	ptr = new PERSON [lines];
	
	for (int i = 0; i < lines; i++)
	{		 
		f >> ptr[i].Age;
		f >> ptr[i].Gpa;
		f.getline(ptr[i].Name, 50, '\n');
	}
	
	for (int i = 0; i < lines; i++)	
	cout << "name: " << ptr[i].Name << " age: " <<ptr[i].Age << " gpa: " << ptr[i].Gpa << endl;	
	
return 0;
}

[mobotus]

You get the array size but never actually create the array.

p = new PERSON[size];

Then just don't forget to delete what you new before the end of main.

delete[] p;

[anup30]

mobotus wrote:

You get the array size but never actually create the array.

p = new PERSON[size];

Then just don't forget to delete what you new before the end of main.

delete[] p;

don't you see i used them between line 24 and 29.

i am not writing everything along the way as an assignment - rather showing whats needed. and, when main ends it automatically delets the pointer - its a small program.

[mobotus]

@anup30 I was referring to the OP's code.

[anup30]

okay

[alex067]

Thank you very much, I can't believe I overlooked something that important when dealing with dynamic arrays.

One last question, why do you use ifstream f ("text file")? What is the difference between that and;

fstream f;
f.open("text file", ios::in)

[mobotus]

fstream input and output
ifstream input
ofstream output

[alex067]

Why wouldn't you just use fstream then if it's more powerful?

[anup30]

fstream is summation of ifstream and ofstream.

its similar to many people learn C, while C++ gives more opportunity.

[mobotus]

Same reason why you make some things const. to keep it safe. If you have data you don't want to over-write create an input stream. Then if you try to do something silly the compiler will yell at you.

#include <fstream>
#include <string>

int main(){

	std::string name;
	std::ifstream file;

	file.open("someFile");

	file >> name; //OK
	file << name; //Compile fails

}

[anup30]

or, why do you keep your 100$ note in money bag, while A briefcase gives you more space?