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==An example of multiple base classes.==

<source lang="cpp">#include <iostream>
using namespace std;

class BaseClass1 {
protected:
int x;
public:
void showx() { cout << x << "\n"; }
};

class BaseClass2 {
protected:
int y;
public:
void showy() { cout << y << "\n"; }
};

// Inherit multiple base classes.
class DerivedClass: public BaseClass1, public BaseClass2 {
public:
/* x and y are accessible because they are
protected in BaseClass1 and BaseClass2, not private. */
void set(int i, int j) { x = i; y = j; }
};

int main()
{
DerivedClass ob;

ob.set(10, 20); // provided by DerivedClass
ob.showx(); // from BaseClass1
ob.showy(); // from BaseClass2

return 0;
}</source>
<pre class=codeResult>10
20</pre>

==In cases of multiple inheritance: Constructors are called in order of derivation, destructors in reverse order==

<source lang="cpp">#include <iostream>
using namespace std;

class base {
public:
base() { cout << "Constructing base\n"; }
~base() { cout << "Destructing base\n"; }
};

class derived1 : public base {
public:
derived1() { cout << "Constructing derived1\n"; }
~derived1() { cout << "Destructing derived1\n"; }
};

class derived2: public derived1 {
public:
derived2() { cout << "Constructing derived2\n"; }
~derived2() { cout << "Destructing derived2\n"; }
};

int main()
{
derived2 ob;

// construct and destruct ob

return 0;
}</source>

==Multiple inheritance example==

<source lang="cpp">#include <iostream>
using std::ostream;
using std::cout;
using std::endl;
class Base1 {
public:
Base1( int parameterValue )
{
value = parameterValue;
}
int getData() const
{
return value;
}
protected:
int value;
};
class Base2
{
public:
Base2( char characterData )
{
letter = characterData;
}
char getData() const
{
return letter;
}
protected:
char letter;
};
class Derived : public Base1, public Base2
{
public:
Derived( int integer, char character, double double1 )
: Base1( integer ), Base2( character ), real( double1 ) { }
double getReal() const {
return real;
}
void display()
{
cout << " Integer: " << value << "\n Character: "
<< letter << "\nReal number: " << real;
}
private:
double real;
};

int main()
{
Base1 base1( 10 ), *base1Ptr = 0;
Base2 base2( "Z" ), *base2Ptr = 0;
Derived derived( 7, "A", 3.5 );
cout << base1.getData()
<< base2.getData();
derived.display();
cout << derived.Base1::getData()
<< derived.Base2::getData()
<< derived.getReal() << "\n\n";
base1Ptr = &derived;
cout << base1Ptr->getData() << "\n";
base2Ptr = &derived;
cout << base2Ptr->getData() << endl;
return 0;
}</source>
<pre class=codeResult>10Z Integer: 7
Character: A
Real number: 3.57A3.5
7
A</pre>

==Multiple Inheritance in both private and public way==

<source lang="cpp">#include <iostream>
using namespace std;
class One
{
public:
One(void)
{
cout << "Constructor for One\n";
one = 1;
};
int one;
};
class Two
{
public:
Two(void)
{
cout << "Constructor for Two\n";
two = 2;
};
int two;
};
class Three
{
public:
Three(void)
{
cout << "Constructor for Three\n";
three = 3;
};
int three;
};
class Derived: private One, private Three, public Two
{
public:
Derived(void) : One(), Two(), Three()
{
cout << "Derived constructor called\n"; };
void show_value(void) { cout << one << two << three << endl; };
};
int main(void)
{
Derived my_class;
my_class.show_value();
cout << my_class.two;
}</source>

==Multiple Inheritance to have the features from both parent==

<source lang="cpp">#include <iostream>
using std::cout;
using std::cin;
using std::endl;
class Horse
{
public:
Horse() { cout << "Horse constructor... "; }
virtual ~Horse() { cout << "Horse destructor... "; }
virtual void Whinny() const { cout << "Whinny!... "; }
private:
int itsAge;
};
class Bird
{
public:
Bird() { cout << "Bird constructor... "; }
virtual ~Bird() { cout << "Bird destructor... "; }
virtual void Chirp() const { cout << "Chirp... "; }
virtual void Fly() const
{
cout << "fly! ";
}
private:
int itsWeight;
};
class Pegasus : public Horse, public Bird
{
public:
void Chirp() const { Whinny(); }
Pegasus() { cout << "Pegasus constructor... "; }
~Pegasus() { cout << "Pegasus destructor... "; }
};
const int MagicNumber = 2;
int main(){
Horse* Ranch[MagicNumber];
Bird* Aviary[MagicNumber];
Horse * pHorse;
Bird * pBird;

pHorse = new Pegasus;
pHorse = new Horse;
Ranch[0] = pHorse;
pBird = new Pegasus;
pBird = new Bird;
Aviary[0] = pBird;
Ranch[0]->Whinny();
delete Ranch[0];

Aviary[0]->Chirp();
Aviary[0]->Fly();
delete Aviary[0];
return 0;
}</source>

==multiple inheritance with employees and degrees==

<source lang="cpp">#include <iostream>
using namespace std;
const int LEN = 80;
class student{
private:
char school[LEN];
char degree[LEN];
public:
void getedu(){
cout << " Enter name of school or university: ";
cin >> school;
cout << " Enter highest degree earned \n";
cout << " (Highschool, Bachelor"s, Master"s, PhD): ";
cin >> degree;
}
void putedu() const
{
cout << "\n School or university: " << school;
cout << "\n Highest degree earned: " << degree;
}
};
class employee{
private:
char name[LEN];
unsigned long number;
public:
void getdata(){
cout << "\n Enter last name: "; cin >> name;
cout << " Enter number: "; cin >> number;
}
void putdata() const
{
cout << "\n Name: " << name;
cout << "\n Number: " << number;
}
};
class manager : private employee, private student {
private:
char title[LEN];
double dues;
public:
void getdata(){
employee::getdata();
cout << " Enter title: "; cin >> title;
cout << " Enter golf club dues: "; cin >> dues;
student::getedu();
}
void putdata() const
{
employee::putdata();
cout << "\n Title: " << title;
cout << "\n Golf club dues: " << dues;
student::putedu();
}
};
class scientist : private employee, private student {
private:
int pubs;
public:
void getdata(){
employee::getdata();
cout << " Enter number of pubs: "; cin >> pubs;
student::getedu();
}
void putdata() const
{
employee::putdata();
cout << "\n Number of publications: " << pubs;
student::putedu();
}
};
class laborer : public employee
{
};
int main(){
manager m1;
scientist s1, s2;
laborer l1;

cout << endl;
cout << "\nEnter data for manager 1";
m1.getdata();

cout << "\nEnter data for scientist 1";
s1.getdata();

cout << "\nEnter data for scientist 2";
s2.getdata();

cout << "\nEnter data for laborer 1";
l1.getdata();

cout << "\nData on manager 1";
m1.putdata();

cout << "\nData on scientist 1";
s1.putdata();

cout << "\nData on scientist 2";
s2.putdata();

cout << "\nData on laborer 1";
l1.putdata();
cout << endl;
return 0;
}</source>

==multiple inheritance with English Distances==

<source lang="cpp">#include <iostream>
#include <string>
using namespace std;
class Type{
private:
string dimensions;
string grade;
public:
Type() : dimensions("N/A"), grade("N/A"){ }

Type(string di, string gr) : dimensions(di), grade(gr)
{ }
void gettype(){
cout << " Enter nominal dimensions (2x4 etc.): ";
cin >> dimensions;
cout << " Enter grade (rough, const, etc.): ";
cin >> grade;
}
void showtype() const
{
cout << "\n Dimensions: " << dimensions;
cout << "\n Grade: " << grade;
}
};
class Distance{
private:
int feet;
float inches;
public:
Distance() : feet(0), inches(0.0){ }
Distance(int ft, float in) : feet(ft), inches(in)
{ }
void getdist(){
cout << " Enter feet: "; cin >> feet;
cout << " Enter inches: "; cin >> inches;
}
void showdist() const
{ cout << feet << "\"-" << inches << "\""; }
};
class Lumber : public Type, public Distance {
private:
int quantity;
double price;
public:
Lumber() : Type(), Distance(), quantity(0), price(0.0)
{ }
Lumber( string di, string gr,
int ft, float in,
int qu, float prc ) :
Type(di, gr),
Distance(ft, in),
quantity(qu), price(prc)
{ }
void getlumber()
{
Type::gettype();
Distance::getdist();
cout << " Enter quantity: "; cin >> quantity;
cout << " Enter price per piece: "; cin >> price;
}
void showlumber() const
{
Type::showtype();
cout << "\n Length: ";
Distance::showdist();
cout << "\n Price for " << quantity
<< " pieces: $" << price * quantity;
}
};
int main(){
Lumber siding;
siding.getlumber();
Lumber studs( "2x4", "const", 8, 0.0, 200, 4.45F );

cout << "\nSiding"; siding.showlumber();
cout << "\nStuds"; studs.showlumber();
cout << endl;
return 0;
}</source>

==Resolving Ambiguity in Case of Multiple Inheritance Involving Common Base Classes==

<source lang="cpp">#include <iostream>
using namespace std;
typedef int HANDS;
enum COLOR { Red, Green, Blue, Yellow, White, Black, Brown } ;
class Animal
{
public:
Animal(int);
virtual ~Animal() { cout << "Animal destructor...\n"; }
virtual int GetAge() const { return itsAge; }
virtual void SetAge(int age) { itsAge = age; }
private:
int itsAge;
};
Animal::Animal(int age):
itsAge(age)
{
cout << "Animal constructor...\n";
}
class Horse : public Animal
{
public:
Horse(COLOR color, HANDS height, int age);
virtual ~Horse() { cout << "Horse destructor...\n"; }
virtual void Whinny()const { cout << "Whinny!... "; }
virtual HANDS GetHeight() const { return itsHeight; }
virtual COLOR GetColor() const { return itsColor; }
protected:
HANDS itsHeight;
COLOR itsColor;
};
Horse::Horse(COLOR color, HANDS height, int age):
Animal(age),
itsColor(color),itsHeight(height)
{
cout << "Horse constructor...\n";
}
class Bird : public Animal
{
public:
Bird(COLOR color, bool migrates, int age);
virtual ~Bird() {cout << "Bird destructor...\n"; }
virtual void Chirp()const { cout << "Chirp... "; }
virtual void Fly()const{ cout << "fly! "; }
virtual COLOR GetColor()const { return itsColor; }
virtual bool GetMigration() const { return itsMigration; }
protected:
COLOR itsColor;
bool itsMigration;
};
Bird::Bird(COLOR color, bool migrates, int age):
Animal(age),
itsColor(color), itsMigration(migrates)
{
cout << "Bird constructor...\n";
}
class Pegasus : public Horse, public Bird
{
public:
void Chirp()const { Whinny(); }
Pegasus(COLOR, HANDS, bool, long, int);
virtual ~Pegasus() {cout << "Pegasus destructor...\n";}
virtual long GetNumberBelievers() const
{ return itsNumberBelievers; }
virtual COLOR GetColor()const { return Horse::itsColor; }
virtual int GetAge() const { return Horse::GetAge(); }
private:
long itsNumberBelievers;
};
Pegasus::Pegasus(
COLOR aColor,
HANDS height,
bool migrates,
long NumBelieve,
int age):
Horse(aColor, height,age),
Bird(aColor, migrates,age),
itsNumberBelievers(NumBelieve)
{
cout << "Pegasus constructor...\n";
}
int main()
{
Pegasus *pPeg = new Pegasus(Red, 5, true, 10, 2);
int age = pPeg->GetAge();
cout << "This pegasus is " << age << " years old.\n";
delete pPeg;
return 0;
}</source>

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