Two Identical Code Segments, Different Results

All I need to do is a simple read from a file in the same directory, but for some reason it refuses to work.

It works perfectly fine in this quick test one I made after I had problems, and outputs the number of entries in the text file.

#include <iostream>
using std::cout;
using std::cin;

#include <cstdio>

int main()
    {
    int a;
    int b = 0;
    freopen ("7.txt", "r", stdin);

    while (cin >> a)
        ++b;

    cin.clear();

    fclose (stdin);
    freopen ("7.txt", "r", stdin);

    cout << b << '\n';

    fclose (stdin);
}

EDIT: Wow I'm sorry to everyone who tried wrapping their heads around this. It was pretty late when I posted this, but I thought I finished. Apparently not. Now upon reopening my file to post the code in it, I realize that I moved everything into a f开发者_StackOverflow社区older before, but apparently when I tried to run the actual thing, it saved back outside of the folder, so it couldn't open "7.txt".

Problem solved I guess, sad waste of space seeing as how it wasn't even complete O_o, sorry.

EDIT2: Okay now I'm confused. I had a temp account on this computer, but when I logged into this account to ask a different question, this one as I meant to post it the other night showed up. I wasn't even on this computer while asking it. Not sure why it wasn't posted like that if it was all ready to be though.

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My best "guess" is that you are trying to re-read the same file. If this is the case then you could try this :

std::ifstream file("7.txt");
std::string line = "";
while(std::getline(file, line))
{
  //do something
}
//reset file pointer
file.clear();
file.seekg (0, std::ios::beg);
//re-read file
while(std::getline(file, line))
{
  //do something else
}   

Please try and formulate better questions in the future.

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I have no idea what you're trying to do, but any interaction between freopen, fclose and cin is implementation defined at best (and most likely undefined behavior).