C++

Usage

How to do things using the C++ standard library (stdlib).

Strings

String Interpolation

Reference

#include <iostream>
#include <sstream>
#include <string>

int main() {
    std::string a = "a", b = "b", c = "c";
    // apply formatting
    std::stringstream s;
    s << a << " " << b << " > " << c;
    // assign to std::string
    std::string str = s.str();
    std::cout << str << "\n";
}

Filesystem

Reading and Writing

Reading and writing is done using fstream.
If you don't need r/w, use istream for reading or ostream for writing.

#include <iostream>
#include <fstream>

int main() {
  std::istream my_file("my_file.txt");
  std::string line;
  # Read line by line
  # You can also read using <<
  while (getline(my_file, line)) {
    std::cout << line << std::endl;
  }
  return 0;
}

Regular Expressions

Reference

Threading

Sleep

std::this_thread::sleep_for(std::chrono::milliseconds(1));

Memory

Garbage Collection

Traditional C++ does not have garbage collection.
After using `new` to allocate an object, use `delete` to deallocate it.
You can also use C allocation with `malloc`, `calloc`, `alloca`, and `free`.
If using C++14, you can use shared pointers which does have automatic garbage collection.