Constructor with default argument

example:

#include <iostream>

using namespace std;

class MyClass{
    public:
        MyClass();
        MyClass(string note, const string mName = "DEFAULT_NAME");
        ~MyClass();
    private:
        string myName;
        string myNote;
};

MyClass::MyClass(){
    myName = "default constructor without argument";
    myNote = "";
    cout << "MyClass Constructor: " << myName << endl;

}

MyClass::MyClass(string note, const string mName){
    myName = mName;
    myNote = note;
    cout << "MyClass Constructor: " << myName << " : " << myNote << endl;
}


MyClass::~MyClass(){
    cout << "MyClass Destructor: " << myName << endl;
}

int main()
{
    MyClass myClass1;
    MyClass myClass2("Using default Name");
    MyClass myClass3("with name", "MyClass 3");
    return 0;
}

Constructor and Destructor

example:

#include <iostream>

using namespace std;

class MyClass{
    public:
        MyClass(string mName);
        ~MyClass();
    private:
        string myName;
};

MyClass::MyClass(string mName){
    myName = mName;
    cout << "MyClass Constructor: " << myName << endl;
}

MyClass::~MyClass(){
    cout << "MyClass Destructor: " << myName << endl;
}

int main()
{
    cout << "Hello world!" << endl;
    MyClass myClass("MyClass 1");
    MyClass* myClassPtr = new MyClass("MyClass 2: created using new");
    delete myClassPtr;
    return 0;
}

Array arguments are passed to function by reference

example:

#include <iostream>

using namespace std;

void function(int ArrayPassed[], unsigned len);

int main()
{
    int array[] = {1, 2, 3, 4, 5};
    unsigned length = 5;

    cout << endl << "before fnction()" << endl;
    for(unsigned i = 0; i < length; i++){
        cout << array[i] << " ";
    }
    function(array, length);

    cout << endl << "after fnction()" << endl;
    for(unsigned i = 0; i < length; i++){
        cout << array[i] << " ";
    }

    cout << endl;
    return 0;
}

void function(int ArrayPassed[], unsigned len){
    for(unsigned i = 0; i < len; i++){
        ArrayPassed[i] *= ArrayPassed[i];
    }
}

Pass argument to function by value and by reference

example:

#include <iostream>

using namespace std;

void function(int byValue, int& byRef);

int main()
{
    int a = 5;
    int b = 10;
    cout << endl << "before fnction()" << endl;
    cout << "a (byValue) = " << a << endl;
    cout << "b (byRef) = " << b << endl;
    function(a, b);

    cout << endl << "after fnction()" << endl;
    cout << "a (byValue) = " << a << endl;
    cout << "b (byRef) = " << b << endl;
    return 0;
}

void function(int byValue, int& byRef){
    byValue++;
    byRef++;
}

break and continue

example:

#include <iostream>

using namespace std;

int main()
{
    cout << endl << "the loop break when i = 5" << endl;
    for(int i = 1; i < 10; i ++){
        if (i == 5) break;
        cout << i << endl;
    }

    cout << endl << "the loop skip 5 with continue" << endl;
    for(int i = 1; i < 10; i ++){
        if (i == 5) continue;
        cout << i << endl;
    }
    return 0;
}

bool test ? true : false

#include <iostream>

using namespace std;

int main()
{
    cout << (true ? "It's True" : "It's False") << endl;
    cout << (false ? "It's True" : "It's False") << endl;
    return 0;
}

namespace

#include <iostream>

using namespace std;


namespace myspace {
  int x;
  string s;
}

namespace myspace2 {
  string s2;
}

using namespace myspace2;

int main()
{
  myspace::x = 5;
  myspace::s = "Hello!";
  cout << myspace::s << endl;

  s2 = "Hello 2";
  cout << s2 << endl;

  return 0;
}