HELP NEEDED in creating a program using fstream...absolutely no idea how to do it

Iswandy · 01-31-2010, 11:04 PM

a)using notepad,prepare a text file with marks for 8 students on seperate lines. The program will then read this file and store all the marks into an array.
b)It will then calculate the average marks.
c)Finally, displays all the marks and average marks on the screen.

THKS!!

would you be kind enough to give me the workout solutions...need help in this...thks lots

Aquarius_Girl · 02-01-2010, 12:41 AM

What's so difficult about it ?

Example of reading from a file using fstream:
http://www.codersource.net/cpp_file_io.html

fstream man:
http://www.cplusplus.com/reference/iostream/fstream/

Have U tried anything so far ? Be kind enough to post it here !!

Try reading the above 2 links, try a small program and then if u face problems, feel free to report back..

Read this post too:
http://www.linuxquestions.org/questi...line-771427/#2

Iswandy · 02-01-2010, 07:33 AM

Hmmm this is what i got....help me to check if there are errors and whether is it the correct approach...(refer to question above)

#include <iostream>
#include <fstream>

using namespace std;

int main () {

double marks[8],sum=0,average;
int i,size=0,;
ifstream myfile;

myfile.open ("SPROG.txt");

while( size < 8 && myfile >> marks[size] )
++size;

for(i=0;i<8;i++)
{
myfile >> marks[8];
cout << "Student " << i+1 << " scored " << marks[i] << " marks." << " \n\n";

}
for(i=0;i<8;i++)
{
myfile >> marks[8];
sum +=marks[i] ;
}

average = sum /8.0;
cout << "\nThe average mark is " << average << endl;

myfile.close();

return 0;
}

MTK358 · 02-01-2010, 07:39 AM

You should put code in [code] tags, it will print in a monospaced font.

It looks like this

Code:

Code tags

And you should also indent your code.

Nylex · 02-01-2010, 07:42 AM

Quote:

Originally Posted by Iswandy

Hmmm this is what i got....help me to check if there are errors and whether is it the correct approach...(refer to question above)

#include <iostream>
#include <fstream>

using namespace std;

int main () {

double marks[8],sum=0,average;
int i,size=0,;
ifstream myfile;

myfile.open ("SPROG.txt");

while( size < 8 && myfile >> marks[size] )
++size;

for(i=0;i<8;i++)
{
myfile >> marks[8];
cout << "Student " << i+1 << " scored " << marks[i] << " marks." << " \n\n";

}
for(i=0;i<8;i++)
{
myfile >> marks[8];
sum +=marks[i] ;
}

average = sum /8.0;
cout << "\nThe average mark is " << average << endl;

myfile.close();

return 0;
}

Why do you need the while loop and why do you need two for loops? Also, you need to check where you're storing the input - for one thing, C/C++ arrays are indexed from 0, so the last index of an N element array will be N - 1, not N.

carbonfiber · 02-01-2010, 08:22 AM

Homework?

There are various things wrong with your code, but I'm curious, what do you think this is supposed to do:

Code:

while( size < 8 && myfile >> marks[size] )

Aquarius_Girl · 02-02-2010, 01:33 AM

Quote:

Originally Posted by Iswandy

Hmmm this is what i got....help me to check if there are errors and whether is it the correct approach...(refer to question above)

1. I tested your program, It is working correctly, so what's the problem now ?

2. PUT COMMENTS IN YOUR CODE SO THAT IT BECOMES EASIER FOR MEMBERS TO UNDERSTAND WHAT U ARE TRYING TO DO !!

3. Put your code in code tags.

MTK358 · 02-02-2010, 07:34 AM

Quote:

Originally Posted by anishakaul

2. PUT COMMENTS IN YOUR CODE SO THAT IT BECOMES EASIER FOR MEMBERS TO UNDERSTAND WHAT U ARE TRYING TO DO !!

3. Put your code in code tags.

Indent it, too.

Not indented:

Code:

int main()
{
int i;
for(i=0; i<10; i++)
{
printf("Hello%d\n", i);
}
return 0;
}

Indented:

Code:

int main() {
    int i;
    for(i=0; i<10; i++) {
        printf("Hello%d\n", i);
    }
    return 0;
}