Help with loop

The while loop does an extra iteration, and I don't know why. E.g. if there are only 2 lines in the file it is reading, it prints out the last price and quantity twice, and adds their product to sub. I think it prints out whitespace before that.

fin is an ifstream object. If I change the while condition to (!EOF), the file is not read at all.

I suspect that it has something to do with getline (fin, prodDesc), but prodDesc is a string that may contain spaces, so I don't know how else to read it in.

Any suggestions? My head is swimming.

-->Mariana

Code:

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//this is part of a program that reads from a file
// and outputs a billing invoice

void processOrder(float&sub)
       
        {
       
        sub=0;
       
        do
        {
                fin>>code>>price>>quantity;
                getline (fin, prodDesc);
                total = price * quantity;
                cout<<fixed<<showpoint<<setprecision(2)
                        <<setw(20)<<left<<code
                        <<setw(20)<<left<<prodDesc
                        <<setw(15)<<price
                        <<setw(15)<<quantity
                        <<setw(15)<<total;
                sub += total;
        }while(fin);

        cout<<setw(30)
                <<"Total order: $"
                <<setprecision(2)
                <<setw(15)
                <<fixed<<showpoint
                <<sub<<endl;
       
        }

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A variation of the eof() problem discussed in the FAQ

Try

Code:

---

while ( fin>>code>>price>>quantity ) {
        getline (fin, prodDesc);
        total = price * quantity;
        cout<<fixed<<showpoint<<setprecision(2)
                <<setw(20)<<left<<code
                <<setw(20)<<left<<prodDesc
                <<setw(15)<<price
                <<setw(15)<<quantity
                <<setw(15)<<total;
        sub += total;
}

---

Thank you!

I actually asked a friend for help, and we ended up using the return value of getline() to break it up.

Code:

---

//Reads from file, calculates subtotal
void processOrder(float&sub)
       
        {
       
        sub=0;
       
        do
        {
                fin>>code>>price>>quantity;
                if (getline (fin, prodDesc) != 0)
                {
                total = price * quantity;
                cout<<fixed<<showpoint<<setprecision(2)
                        <<setw(10)<<left<<code
                        <<setw(20)<<left<<prodDesc
                        <<setw(10)<<right<<price
                        <<setw(15)<<quantity
                        <<setw(15)<<total<<endl;
                sub += total;
                }
        }while(fin);

        cout<<setw(55)
                <<"Total order: $"
                <<setprecision(2)
                <<setw(15)
                <<fixed<<showpoint
                <<sub<<endl;
       
        }

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