#includeIn the above example, we open a file named "data.txt" and read the first two characters from the file. If we realize that we didn't want to read the second character, we can use the `unget()` method to return it to the stream. Then, when we call `file >> c2` again, it will read the second character from the stream again. The `ifstream::unget()` method is part of the standard C++ library, so you don't need to install any additional libraries to use it.#include int main() { std::ifstream file("data.txt"); if (file.is_open()) { char c1, c2; file >> c1; file >> c2; std::cout << "Read characters: " << c1 << "," << c2 << std::endl; file.unget(); std::cout << "Unget last character." << std::endl; file >> c2; std::cout << "Read character: " << c2 << std::endl; file.close(); } else { std::cout << "Failed to open file." << std::endl; } return 0; }