Loops are not executing properly in my program! ! Can someone help me out please! ! !

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My loop keeps on repeating inspite of typing N=1.

here is the code..

C++

void club::enterdata()
{
std::cout<<"Enter details";
std::cin>>mno>>memname>>activity;

this is the function... and this is the funcion in which this function is called..

C++

void club::writeinto()
{
    club c{};
    int N, i = 0;
    std::ofstream fout( "project.dat", std::ios::binary );
    if( ! fout )
    {
        std::cout<<"Error";
    }
    while(!fout.eof())
    {
        std::cout << "Enter the number of records to be entered";
        std::cin >> N;
        for(i=0;i<=N;i++)
        {
            c.enterdata();
        }
        fout.write( (char*)&c, sizeof(c) );
    }
    fout.close();
}

here is the output..

Enter the number of records to be entered 1
Enter details 12 hka abc
Enter details

Pls help me out..

What I have tried:

Tried to change the position of the brackets...

Posted 28-Sep-18 4:45am

Member 14001096

Updated 28-Sep-18 6:21am

Rick York

v2

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jeron1 28-Sep-18 11:44am

Is it possible to use a debugger and set a breakpoint in your code and step through each line to see the values of i and N? You could also I suppose, cout the value of N and i in some places to see their value change, or to see which portions of code are being executed.

Richard Deeming 3-Oct-18 15:34pm

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

If N is 1, how many times do you think that loop will execute?

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Rick York · Accepted Answer · 2018-09-28T05:19:00

Solution 1

Why do you have this : "while(!fout.eof())" ?

I think that is your problem. There is NO reason to do that. I have been working with C and C++ for thirty years and I have never checked for EOF on an output file while writing to it. EVER. I can't think of any reason to, only reasons NOT to.

Posted 28-Sep-18 5:19am

Rick York

Comments

Member 14001096 28-Sep-18 14:30pm

As a part of school project, this "while(!fout.eof) is mandatory..

KarstenK · Accepted Answer · 2018-09-28T06:21:00

You should learn to use the debugger, you would have seen your mistake in the first run. Reading the documentation is also helping.

Your for loop has the problem that always the C is overwritten before written to the file.

C++

for(i=0;i<=N;i++)
{
    c.enterdata();
    fout.write( (char*)&c, sizeof(c) );
}

tip: make more detailed I/O for each member in enterdata() and write the data as csv text in the file, so you can better check and reload it.