C++ Files

Read and write files with fstream.

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Include <fstream>:

std::ofstream out("file.txt"); writes; use << like cout.
std::ifstream in("file.txt"); reads; use std::getline(in, line) or >>.
Files close automatically when the stream object goes out of scope (RAII).

Key Takeaways: C++ Files

Mastering C++ Files helps you write clean and reliable C++ code. Follow standard conventions, test edge cases, and keep logic simple. Try running the code example below and complete the exercises to build confidence.

C++ Files Code Example

C++

#include <iostream>
#include <fstream>
#include <string>

int main() {
    {
        std::ofstream out("scores.txt");
        out << "Ali 81\nSara 94\nUsman 67\n";
    }   // file is closed here

    std::ifstream in("scores.txt");
    std::string name;
    int score, best = 0;
    std::string bestName;
    while (in >> name >> score) {
        if (score > best) { best = score; bestName = name; }
    }
    std::cout << "Top: " << bestName << " (" << best << ")\n";
    return 0;
}

Output