Why are my files not opening?

[alvinblee]

#include <fstream>
#include <iostream>
#include <cstdlib>
using namespace std;

int main()
{
ifstream in_stream;
ifstream in_stream2;
ofstream out_stream;
int num1;
int num2;



in_stream.open("LabInput3-3.txt");
if(in_stream.fail())
{
cout << "File would not open.";
exit(1);
}
in_stream2.open("LabInput3-4.txt");
if(in_stream2.fail())
{
cout << "File would not open.";
exit(1);
}
out_stream.open("LabOutput.txt");
if(out_stream.fail())
{
cout << "File would not open.";
exit(1);
}
while(!in_stream.eof())
{
bool smaller = false;
in_stream >> num1;
while(!in_stream2.eof())
in_stream2 >> num2;
if(num1 < num2)
{
out_stream << num1;
smaller = true;
}
if(smaller == true);
{
out_stream << num2;
}
}
in_stream.close();
in_stream.clear();
in_stream2.close();
in_stream2.clear();
out_stream.close();




return 0;
}

[TheIdeasMan]

Hi,

Please always use code tags :

http://www.cplusplus.com/articles/z13hAqkS/

Are your files in the same directory as the code ?

Some other things:

Don't loop on eof, just use the stream:

while(in_stream) {
}

And this:
if(smaller == true); // <----remove semicolon

[alvinblee]

Hi,

Sorry, I'm a beginner.
Fixed the semicolon and the loop.
I just put the files in the src folder where the code is, but it still doesn't open.

[alvinblee]

int main() 
{
	ifstream in_stream;
	ifstream in_stream2;
	ofstream out_stream;
	int num1;
	int num2;



	in_stream.open("LabInput3-3");
	if(in_stream.fail())
	{
	    cout << "File would not open.";
	    exit(1);
	}
	in_stream2.open("LabInput3-4");
	if(in_stream2.fail())
	{
	    cout << "File would not open.";
	    exit(1);
	}
	out_stream.open("LabOutput");
	if(out_stream.fail())
	    {
	        cout << "File would not open.";
	        exit(1);
	    }
	while(in_stream)
	{
	    bool smaller = false;
	    in_stream >> num1;
	while(in_stream2)
	    in_stream2 >> num2;
	if(num1 < num2)
	{
	    out_stream << num1;
	    smaller = true;
	}
	if(smaller == true)
	{
	    out_stream << num2;
	}
	}
	in_stream.close();
    in_stream.clear();
    in_stream2.close();
    in_stream2.clear();
    out_stream.close();
    return 0;
}

[TheIdeasMan]

You should be able to do this:

ifstream in_stream("LabInput3-3.txt");

Also, does the while on line 33 need braces for lines 34 to 43?

Edit: When posting code, post all of it - the include files etc. This is so we can compile it with the cpp.sh gear icon on the top right of the code.

[alvinblee]

I put braces around the lines and now it builds but instead of displaying "File would not open," the whole program terminates. I checked the output file for any characters but it's empty.

[TheIdeasMan]

Are you using windows? The terminal is probably closing before you see anything, try commenting out the exit statements.

Not sure why the files not opening. I will have a try on my system and see what happens.

[alvinblee]

Oh ok, the output file had some characters OUTSIDE of the src file.

Inside of the 3-3 file is:
6 10 15 22 33 77 88 99
Inside of the 3-4 file is:
30 40 50 60 62 89

but the output file is:
630640650660662689689

How could I change my code so it arranges both the 3-3 and the 3-4 file so it is smallest to largest?

[TheIdeasMan]

Ok, The input files need to be in the same directory as the executable file (my bad earlier), then it should work. I managed to get it working on my system doing this :+)