c++ my counter adds an extra count - c++

Question

I am new to programming and trying to teach myself but my counter is displaying one more than it should. it should be displaying 22, but it is displaying 23.
#include <iostream>
#include <fstream>
#include <string>
#include <iomanip>
using namespace std;
//Main and variable data type initializing
void main()
{ float c,l,x,y,z;
int count;
string input, output;
string finput, foutput;
fstream i,o; //i = input file; o = output file;
//Getting the name of the files
cout << "XZY Multiply Program\n" << endl;
cout << "Enter the input file name: c:/";
cin >> input;
cout << "Enter the output file name: c:/";
cin >> output;
//inserts the beginning of the file and file extension.
finput = "c:/" + input;
foutput = "c:/" + output;
//Opens files
i.open(finput.data(),ios::in);
o.open(foutput.data(),ios::out);
//Initialize count and sum of variables
count = 0;
x=0;
y=0;
z=0;
//loop through input file
while(!i.eof() && !o.eof())
{ count++;
if (i.good() && o.good())
{
i >> c;
i >> l;
o << fixed << showpoint << setprecision(4);
o << setw(7) << c;
o << setprecision(2);
o << setw(9) << l;
o << setprecision(3);
o << setw(10) << (l*c) << endl;
// Adds columns
x = x+c;
y = y+l;
z = z+(l*c);
}
else
{
cout << "no good";
}
}
i.close();
o.close();
//Display the output of the counter and Sums of columns
cout << fixed << showpoint << setprecision(2);
cout << "\n" << count << " lines in file " << endl;
cout << "X sum = " << setw(8) << right << x << endl;
cout << "Y sum = " << setw(8) << right << y << endl;
cout << "Z sum = " << setw(8) << right << z << endl;
}
7.2830 84.40
9.1327 124.02
7.2619 133.16
6.2527 43.96
4.2160 24.08
5.2724 57.80
5.2025 73.89
-9.9500 80.53
0.2790 -12.43
2.2115 3.37
3.1222 13.63
16.2413 223.01
-4.2026 33.78
-7.1914 42.89
4.1417 53.42
6.1714 61.66
9.2516 73.68
15.2419 383.66
6.2715 93.53
-3.2016 3.46
12.2013 213.63
3.1824 23.85

Answer 1

Using .eof() or .good() as a loop condition almost always produces buggy code, as it does in this case.
Rather, perform the input and check its result in the loop condition, like so:
while(i >> c >> l)
{ count++;
o << fixed << showpoint << setprecision(4);
o << setw(7) << c;
...
References:
Why is iostream::eof inside a loop condition considered wrong?
http://www.parashift.com/c++-faq-lite/input-output.html#faq-15.5

Answer 2

I assume that after reading the last number from the input file the end of file has not been seen, yet. Try adding
if (!i.good()) break;
after each input statement (>>) to prevent the loop body to be executed after a failed input.