Learn C++

Variables are declared like this:

int port = 8333;

You can create one and assign a value later:

int port;
port = 8333;

To make a constant variable whose value cannot change:

const int port = 8333;

There are several variable types:

int, float, double, char, bool

Functions are declared like this:

void hello() {
  cout << "Hello World"; // print a string to output
}

Functions are declared like this:

// `void` means the function does not return anything
void hello() {
  cout << "Hello World"; // print a string to output
}

You can use them like this:

int add(int a, int b) {
   return (a + b);
}

cout << "The sum of 1 + 2 = " << add(1, 2);

You can create more complex data types:

class Blockchain {
  public:
    string name;
    int port;
}

// create an object
Blockchain bitcoin;

// assign values to it
bitcoin.name = "Bitcoin";
bitcoin.port = 8333;