I am unable to figure out how to check to see if there is more data in the file. I have a input file, where the last two lines are just new lines with new data. When I run my code, I get the last line of data in the file sent through the program twice. I will first put in my code, then followed by the input from the file. I want to know how, to see if there is actually more data or just empty lines.

```
#include <iostream>
#include <cmath> // able to use math functions
#include <fstream> // able to send and recieve data from files
using namespace std;
ofstream outfile; // declarition of in and out files
ifstream infile;
void lines(int &line1, int &line2, int &line3); // prototypes
char valid(int line1, int line2, int line3);
char right(int line1, int line2, int line3);
void output(int a, int b, int c, char x, char y);
int main()
{
outfile.open("triangleout.out"); //open outfile
if (!outfile) // check outfile is open
{
outfile << "Output file did not open.\n";
return 1;
}
infile.open("triangle2.txt"); // open infile
if (!infile) // check infile is open
{
outfile << "Input file did not open.\n\n";
return 1;
}
int line1, line2, line3; // variables for lines
char r_tri, val_tri; // and calculation
while (!infile.eof()) // loops until all data in the file is
{ // used, eof() is End Of File
// the infile is the name of the file declared
// the '!' means NOT, so do this while we are NOT
// at the end of file
lines(line1, line2, line3);
val_tri = valid(line1, line2, line3); // function calls
r_tri = right(line1, line2, line3);
output(line1, line2, line3, val_tri, r_tri);
outfile << "\n\n";
};
infile.close(); // close the infile
outfile.close(); // close the outfile
return 0;
}
void lines(int &line1, int &line2, int &line3)
{
infile >> line1 >> line2 >> line3; // brings data in from outside
// file, also there is no user
// input
}
char valid(int line1, int line2, int line3)
{
char x;
if ((line1 + line2) >= line3 && (line2 + line3) >= line1 && (line1
+ line3) >= line2)
{
x = 'Y'; // this checks to make sure all three
} // possible variations of the calculation
else
{
x = 'N';
}
if ((line1==0||line2==0||line3==0))
{
x = 'N';
}
return x; // returns a char value of Y or N
}
char right(int line1, int line2, int line3)
{
char y; // declare variables for right angle calculation
int check1, check2, big_check, big;
if (line1 > line2) // 2 big if statements to check which
{ // side is the biggest
check1 = pow(line2,2);
if (line1 > line3)
{
big_check = pow(line1,2); // check calculations raise the
check2 = pow(line3,2); // desired variables to the
} // power of 2
else
{
big_check = pow(line3,2);
check2 = pow(line1,2);
}
}
else
{
check1 = pow(line1,2);
if (line2 > line3)
{
big_check = pow(line2,2);
check2 = pow(line3,2);
}
else
{
big_check = pow(line3,2);
check2 = pow(line2,2);
}
}
if (big_check == check1 + check2)
{ // this checks thats the biggest side squared is
y = 'Y'; // equal to the two smaller sides squared
}
else
{
y = 'N';
}
return y;
}
void output(int a, int b, int c, char x, char y)
{
outfile << "A triangle with 3 sides, at " << a << ", " << b;
outfile << ", " << c << ", is ";
// outputs everything
if (x == 'Y')
{
outfile << "a valid trinalge.";
if (y == 'Y')
{
outfile << " Also, this is a right triangle.";
}
else
{
outfile << "However, it is not a right triangle.";
}
}
else
{
outfile <<"not a valid triangle and hence not a right triangle.";
}
}
```

Now here is the input file(exactly):

10 8 4

4 8 10

90 200 125

5 12 6

90 181 90

1588 2300 4000

90 90 180

5 25 45

6000 7500 7000

1 1 1

1000 1 1000

50 20 5

1 1000 2500

0 0 0

(empty line, just so you understand)

(empty line)

Please help. I am new to programming, so go easy.