ifstream

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

int main() {
    std::ifstream inputFile;
    std::string fileName = "example.txt";

    inputFile.open(fileName);

    if (inputFile.is_open()) {
        std::string line;
        while (getline(inputFile, line)) {
            std::cout << line << std::endl;
        }

        inputFile.close();
    } else {
        std::cerr << "Unable to open file: " << fileName << std::endl;
    }

    return 0;
}