txt Files as a beginner

[slice of life]

Solved

[Ganado]

Since you don't know the number of elements you're going to be dealing with at compile time, this a good place to use an std::vector.

if your file looks something like this

63 81 100 11 42 79 ...

then it would be something like this:

std::ifstream f("grade.txt");

std::vector<int> grades;
int grade = -1;
while (f >> grade)
{
    grades.push_back(grade);
} 

The >> operator skips through whitespace and puts each piece of data into a variable.

After that, displaying the scores, totals, and average is unrelated to the text file, you must now iterate through your vector.

[slice of life]

solved

[SuperStrange]

I modified your code a little, here it is

#include <iostream>
#include <fstream>
#include <vector>

using namespace std;

int main()
{
	std::ifstream f("grade.txt");

	vector<int> grades;
	int grade = -1;
	while (f >> grade)
	{
		grades.push_back(grade);
	}
	int total = 0;
	for(int i = 0; i < grades.size(); ++i)
	{
		total += grades[i];
	}
	cout << "The total grade is " << total << endl;
	cout << "And the average grade is " << total/grades.size() << endl;
}

The first mistake is you forgot to include <vector>, but you use it.
Second is that you forgot to write the main() function...everything else, except you missing ";" in this line

double vector

is good)

[slice of life]

solved

[Ganado]

Add this

int main()
{
    std::ifstream f("grade.txt");
    if (!f.is_open())
    {
        std::cout << "Error: failed to open file.\n";
        return 1;
    }
    //the rest...
}

Is this your first time trying to work with a file?
possible solutions:
* Make sure your file is in the same directory as your executable (or if you're using an IDE that does things differently, wherever the IDE reads resources from).
* Depending on your OS, make sure another program using your file isn't preventing your program from accessing it.

grades.size() is 0 at this point, thus you're trying to divide by 0.

[slice of life]

solved

[Ganado]

Learning how to figure out what compiler errors mean can be very useful.

14	16	test.cpp	[Error] redeclaration of 'std::ifstream f'

You have the line std::ifstream f("grade.txt"); twice in your code, remove the second time you declare it. Hope it can compile now, and it should display an error if it can't open your file correctly.

[slice of life]

solved

[slice of life]

Solved

[Ganado]

The C++ part of you issue seems to be working fine now, there's something weird with what you're doing in your Windows OS or cmd, so I can't really help you there. What steps are you taking to run your executable, and what windows OS are you on?

I would try enter part of

CMD.EXE was started with the above path as the current directory.
UNC paths are not supported. Defaulting to Windows directory.

into a google search or something to try to find some relevant info, I have never had a problem like that using cmd so I probably can't help further.

http://stackoverflow.com/questions/23673632/cmd-exe-was-started-with-the-above-path-as-the-current-directory-unc-paths-are

Also, for next time you should use code tags for code posting, the [<>] button under Format.

Edit: If you can't get it to work, a temporary fix (don't do this in good code, as it makes it non-portable) would be to give the absolute path to your file
ex:
std::fstream f("C:/programming/files/grade.txt");