Overloading

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()

function overloading ?

operator overloading function overloading

()

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Function Overloading

3

(Signature)

Animal::Animal(int a, const char * cat = Elephant){ age = a; strcpy(category,cat);}

Animal ob1(16);

Animal ob2(18,Dog);

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print()

print()

3_Print.cpp

()

( + = )

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class frac {} ;int main() {

int x=5, y =3, z ; z = x + y ; // =+int a[10], b[10], c[10]; c = a + b ; // ???frac f1(3,5), f2(2, 5), f3 ;f3 = f1 + f2 ; // 3/5 + 2/5 = 1, ?return 0;

}

+= frac

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int main() {

frac f1(3,5), f2(2, 5) , f3 ;

f3.set(f1.add(f2)) ; // f3 = f1 + f2 ;

if (f1.great_equal(f2)) // f1 >= f2

cout = f2 ;

cout

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+, -, *, /, =, >, , =,

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C++

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C++

10

C++

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class Coord {

int x, y ;

} ;

int main() {

Coord o1(10,10), o2(5,3), o3 ;

o3 = o1 + o2; // o3 (15, 13)

o3.print() ; //later, you can use cout

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+= (1/4)class Coord {

int x, y ;

} ;

int main() {

Coord o1(10,10), o2(5,3), o3 ;

o3.set(o1.add(o2)); // o3 = o1 + o2 ;

o3.print() ; //later, you can use cout

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+= (2/4)class Coord {

int x, int y;

public:

Coord(){}

Coord(int a, int b){x=a; y=b;}

Coord add(Coord c) {

Coord temp ;

temp.x = x + c.x ;

temp.y = y + c.y ;

return temp ;

}

void set(Coord c) {

x = c.x; y=c.y;

}

void print(){cout

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3_NotYet.cpp

#include

using namespace std;

class Coord {

int x,y;

public:

Coord();

Coord(int, int);

void print();

} ;

Coord::Coord(int a,int b)

{

x=a;

y=b;

}

C++

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+= (3/4)

class Coord {

Coord operator+(Coord c) { //add()

Coord temp ;

temp.x = x + c.x ;

temp.y = y + c.y ;

return temp ;

}

void operator=(Coord c) { // set()

x = c.x; y=c.y;

}

} ;

void main() {

Coord o1(10,10), o2(5,3), o3 ;

// o3.set(o1.add(o2));

o3.operator=(o1.operator+(o2));

}

C++

+= (4/4)

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class Coord {

Coord operator+(Coord c) { //add()

coord temp ;

temp.x = x + c.x ;

temp.y = y + c.y ;

return temp ;

}

void operator=(Coord c) { // set()

x = c.x; y=c.y;

}

} ;

void main() {

Coord o1(10,10), o2(5,3), o3 ;

// o3.set(o1.add(o2));

// o3.operator=(o1.operator+(o2);

o3 = o1 + o2 ;

}

C++

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o3 = o1 + o2 ;

o3.operator=(o1.operator+(o2)) ;

o3 = o1.operator+(o2) ;

C++

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(operator function)

class {// overload X operatorX() { }

};

C++

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classclass Coord {

Coord operator+(Coord c) ;

void operator=(Coord c) ;

} ;

Coord Coord::operator+(Coord c) {.}

void Coord::operator=(Coord c) {}

C++

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(3_OpOverload.cpp)

int main() {

Coord o1(10,10), o2(5,3), o3 ;

o3=o1+o2; // o3 = o1 + o2 ;

o3.print() ; //later, you can use cout

Call by reference

class Coord {

Coord operator+(const Coord& c) ;

void operator=(const Coord& c) ;

} ;

Coord Coord::operator+(const Coord& c) {}

void Coord::operator=(const Coord& c) {}

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?

C++

operator+temp, operator=, Coord cconst,

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Call by reference (3_reference.cpp)

reference

int main() {

Coord o1(10,10), o2(5,3), o3;

o3=o1+o2; // o3 = o1 + o2 ;

o3.print(); //later, you can use cout

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o4 = o1+o2+o3;

o4.operator=(o1+o2+o3);

o4.operator=(o1.operator+(o2+o3));

o4.operator=(o1.operator+(o2.operator+(o3)));

o1=o2=o3;

o1.operator=(o2=o3);

o1.operator=(o2.operator=(o3));

C++

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Coord operator+(Coord c) { //add()Coord temp ;temp.x = x + c.x ; temp.y = y + c.y ;return temp ;

}

o1.operator+(o2+o3);

void operator=(Coord c) { // set()x = c.x; y=c.y;

}

o1.operator=(o2=o3);

Coord Coord::operator=(Coord c) {

x = c.x;

y=c.y;

return *this;

}

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(3_ContAdd.cpp)

int main() {

Coord o1(10,10), o2(5,3), o3(3,2),o4,o5 ;

o5=o4=o1+o2+o3; // o3 = o1 + o2 ;

o5.print() ; //later, you can use cout

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(Binary Operators)

: +, -, *, /, =, +=, -=,.,

: >, =,

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(1/2)

class Coord {

int x, y ;

public:

Coord() {x = 0 ; y=0 ; }

Coord(int i, int j) { x=i; y=j;}

bool operator==(const Coord& ob2) ;

};

int main() { Coord o1(10,10); o2(5,3) ;

if (o1 == o2) cout

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(2/2)

bool Coord::operator==(const Coord& ob2) {

return (this->x==ob2.x) && (this->y==ob2.y);

}

C++

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== (3_Logic.cpp)

int main() {

Coord o1(10,10), o2(3,5), o3;

if (o1==o2)cout

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++, --, +, -

int main() {

Coord o1(10, 10), o2 ;o2 = ++o1 ; o1.print() ; // ++, prefixo2 = o1++ ; o1.print() ; //++, postfixreturn 0;

}

o1.operator++()

C++

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prefixpostfix ++class Coord {

int x, int y;

public:

Coord(){}

Coord(int a, int b){x=a; y=b;}

Coord& operator++() { // prefix ++

x++; y++ ; return *this;

}

Coord operator++(int) {//postfix ++

Coord temp = *this ;

x++; y++ ;

return temp ;

}

}

++o1 ;

C++

++--,

Q: void operator++()?

o1++ ;

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Operator ++ ++d1

d1.operator++()

Date &operator++()

d1++

d1.operator++(0)

Date operator++(int)

C++

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++ (3_AddAdd.cpp)

int main() {Coord o1(10,10),o2;

cout

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o3 = o1+o2 ; o3 = o1.operator+(o2) ;

o3 = o1+5 ; o3 = o1.operator+(5) ;

o3 = 10 + o2 ; o3 = 10.operator+(o2);

?????

!

C++

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#include

class Coord {

int x, y ;

} ;

Coord operator+(Coord ob1, Coord ob2) {

return Coord(ob1.x+ob2.x, ob1.y+ob2.y) ;

}

void main() {

Coord o1(10,10), o2(5, 3), o3;

o3 = o1 + o2 ;

}

// o3 = operator+(o1, o2) ;

operator+(Coord, Coord)Q1:class Coord?Q2:x, y ?

friend Coord operator+(Coord ob1, Coord ob2) ;

C++

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10+o2class Coord{

int x, y ;

public:

Coord(){x=0;y=0;}

Coord(int a){x=a;y=a;}

Coord(int a, int b){x=a;y=b;}

friend Coord operator+(Coord ob1, Coord ob2);

void print(){cout

operator+() 12

1

2

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>

> ob1

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3_OutputOverloading.cpp print()