C++
Usage
How to do things using the C++ standard library (stdlib).
Strings
String Interpolation
#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
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.