# strstream *** **1. Redirecting Standard Output** ```cpp #include #include int main() { std::stringstream buffer; std::streambuf* old_buffer = std::cout.rdbuf(buffer.rdbuf()); std::cout << "Hello, world!" << std::endl; std::string output = buffer.str(); std::cout.rdbuf(old_buffer); std::cout << output; return 0; } ``` **2. String Formatting** ```cpp #include #include int main() { std::stringstream ss; ss << std::setw(10) << std::left << "Hello" << std::setw(10) << std::left << "World"; std::string formatted_string = ss.str(); } ``` **3. Tokenization** ```cpp #include #include int main() { std::stringstream ss("Hello World"); std::vector tokens; std::string token; while (std::getline(ss, token, ' ')) { tokens.push_back(token); } } ``` **4. Input Buffering** ```cpp #include #include int main() { std::stringstream buffer; buffer << "Hello World" << std::endl; std::string line; while (std::getline(buffer, line)) { std::cout << line << std::endl; } } ``` **5. CSV Parsing** ```cpp #include #include int main() { std::stringstream ss("John,Doe,123"); std::string name, surname; int age; std::getline(ss, name, ','); std::getline(ss, surname, ','); ss >> age; std::cout << name << " " << surname << ", " << age << std::endl; } ``` **6. XML Parsing** ```cpp #include #include int main() { std::stringstream ss("John123"); std::string tag, name, age; while (ss >> tag) { if (tag == "") { ss >> name; } else if (tag == "") { ss >> age; } } std::cout << "Name: " << name << ", Age: " << age << std::endl; } ``` **7. HTML Parsing** ```cpp #include #include int main() { std::stringstream ss("

Hello World

"); std::string tag, text; while (ss >> tag) { if (tag == "

") { std::getline(ss, text, '

'); } } std::cout << "Header: " << text << std::endl; } ``` **8. Converting Numbers to Strings** ```cpp #include #include int main() { int number = 123; std::stringstream ss; ss << number; std::string number_string = ss.str(); } ``` **9. Converting Strings to Numbers** ```cpp #include #include int main() { std::string number_string = "123"; std::stringstream ss(number_string); int number; ss >> number; } ``` **10. Manipulating Strings** ```cpp #include #include int main() { std::string input_string = "Hello world!"; std::stringstream ss(input_string); ss << "This is a modified string"; std::string modified_string = ss.str(); } ``` **11. Joining Strings** ```cpp #include #include int main() { std::vector strings = {"Hello", "world", "!"}; std::stringstream ss; for (const auto& str : strings) { ss << str; } std::string joined_string = ss.str(); } ``` **12. Splitting Strings** ```cpp #include #include int main() { std::string input_string = "Hello.world.!"; std::vector parts; std::stringstream ss(input_string); std::string part; while (std::getline(ss, part, '.')) { parts.push_back(part); } } ``` **13. Inserting and Removing Characters** ```cpp #include #include int main() { std::string input_string = "Hello"; std::stringstream ss(input_string); ss << ", world!"; std::string modified_string = ss.str(); } ``` **14. Logging Messages** ```cpp #include #include int main() { std::stringstream ss; ss << "Error: File not found"; std::cerr << ss.str() << std::endl; } ``` **15. Serializing Objects** ```cpp #include #include class Person { public: Person(const std::string& name, int age) : name(name), age(age) {} std::string Serialize() { std::stringstream ss; ss << name << "," << age; return ss.str(); } static Person Deserialize(const std::string& serialized_string) { std::stringstream ss(serialized_string); std::string name, age_string; std::getline(ss, name, ','); std::getline(ss, age_string); int age = std::stoi(age_string); return Person(name, age); } private: std::string name; int age; }; ``` **16. Generating Random Strings** ```cpp #include #include #include int main() { std::random_device rd; std::mt19937 gen(rd()); std::uniform_int_distribution dist(0, 9); std::stringstream ss; for (int i = 0; i < 10; i++) { ss << dist(gen); } std::string random_string = ss.str(); } ``` **17. Hashing Strings** ```cpp #include #include #include int main() { std::string input_string = "Hello world!"; std::stringstream ss; ss << input_string; boost::crc_32_type crc; crc.process_bytes(ss.str().c_str(), ss.str().length()); std::cout << crc.checksum() << std::endl; } ``` **18. Encrypting Strings** ```cpp #include #include #include int main() { std::string input_string = "Hello world!"; std::stringstream ss; std::string hash; hash.resize(SHA256_DIGEST_LENGTH); SHA256_CTX sha256; SHA256_Init(&sha256); SHA256_Update(&sha256, input_string.c_str(), input_string.length()); SHA256_Final((unsigned char*)hash.data(), &sha256); std::cout << hash << std::endl; } ``` **19. Decoding Strings** ```cpp #include #include #include int main() { std::string encoded_string = "SGVsbG8gd29ybGQh"; std::stringstream ss; ss << encoded_string; std::string decoded_string; base64_decode(ss.str(), decoded_string); std::cout << decoded_string << std::endl; } ``` **20. Obfuscating Strings** ```cpp #include #include #include int main() { std::string input_string = "Hello world!"; std::stringstream ss; std::for_each(input_string.begin(), input_string.end(), [](char& c) { c = c ^ 0x01; }); ss << input_string; std::string obfuscated_string = ss.str(); } ``` **21. Compressing Strings** ```cpp #include #include #include int main() { std::string input_string = "Hello world!"; std::stringstream ss; z_stream zs; zs.zalloc = Z_NULL; zs.zfree = Z_NULL; zs.opaque = Z_NULL; if (deflateInit(&zs, Z_BEST_COMPRESSION) != Z_OK) { std::cerr << "deflateInit failed" << std::endl; return 1; } zs.avail_in = input_string.length(); zs.next_in = (Bytef*)input_string.data(); std::string compressed_string; while (zs.avail_in > 0) { zs.avail_out = 1024; zs.next_out = (Bytef*)compressed_string.data() + compressed_string.length(); int status = deflate(&zs, zs.avail_out != 0 ? Z_NO_FLUSH : Z_FINISH); if (status != Z_OK && status != Z_STREAM_END) { std::cerr << "deflate failed" << std::endl; deflateEnd(&zs); return 1; } compressed_string.resize(compressed_string.length() + zs.avail_out); } deflateEnd(&zs); ss << compressed_string; } ``` **22. Timestamping Strings** ```cpp #include #include #include int main() { std::stringstream ss; ss << std::chrono::system_clock::now().time_since_epoch().count(); std::string timestamped_string = ss.str(); } ``` **23. Generating Unique IDs** ```cpp #include #include #include int main() { uuid_t uuid; uuid_generate(uuid); std::stringstream ss; ss << uuid; std::string uuid_string = ss.str(); } ``` **24. Converting Strings to Integers** ```cpp #include #include int main() { std::string number_string = "123"; std::stringstream ss(number_string); int number; ss >> number; } ``` **25. Converting Integers to Strings** ```cpp #include #include int main() { int number = 123; std::stringstream ss; ss << number; std::string number_string = ss.str(); } ``` **26. Converting Floating-Point Numbers to Strings** ```cpp #include #include int main() { double number = 123.45; std::stringstream ss; ```