C++/Function/Function Overloaded

Compute area of a rectangle using overloaded functions.

<source lang="cpp">

1. include <iostream>

using namespace std; double rect_area(double length, double width) {

 return length * width;

} double rect_area(double length) {

 return length * length;

} int main() {

 cout  << "10 x 5.8 rectangle has area: ";
 cout << rect_area(10.0, 5.8) << "\n";
 cout  << "10 x 10 square has area: ";
 cout << rect_area(10.0) << "\n";
 return 0;

}

 </source>

Create three functions called prompt( ) that perform this task for data of types int, double, and long

<source lang="cpp">

1. include <iostream>

using namespace std; void prompt(char *str, int *i); void prompt(char *str, double *d); void prompt(char *str, long *l);

int main(void){

 int i;  
 double d;  
 long l;  
    
 prompt("Enter an integer: ", &i);  
 prompt("Enter a double: ", &d);  
 prompt("Enter a long: ", &l);  
    
 cout << i << " " << d << " " << l;  
    
 return 0;  

}

void prompt(char *str, int *i) {

 cout << str;  
 cin >> *i;  

}

void prompt(char *str, double *d) {

 cout << str;  
 cin >> *d;  

}

void prompt(char *str, long *l) {

 cout << str;  
 cin >> *l;  

}

 </source>

function overloading between int and string type

<source lang="cpp">

1. include <iostream>
2. include <string>

using namespace std; int triple(int number); string triple(string text); int main(){

   cout << "Tripling 5: " << triple(5) << "\n\n";
   cout << "Tripling "gamer": " << triple("gamer");
   return 0;

} int triple(int number){

   return (number * 3);

} string triple(string text){

   return (text + text + text);

}

 </source>

Functions differ in number of parameters

<source lang="cpp">

1. include <iostream>

using namespace std; int myFunction(int i); int myFunction(int i, int j); int main() {

 cout << myFunction(10) << " "; // calls myFunction(int i)
 cout << myFunction(4, 5);      // calls myFunction(int i, int j)
 return 0;

} int myFunction(int i) {

 return i;

} int myFunction(int i, int j) {

 return i*j;

}

 </source>

Overload abs() three ways

<source lang="cpp">

1. include <iostream>

using namespace std;

int abs(int n); double abs(double n); int main() {

 cout << "Absolute value of -10: " << abs(-10) << endl;
 cout << "Absolute value of -10.01: " << abs(-10.01) << endl;
 return 0;

} int abs(int n) {

 cout << "In integer abs()\n";
 return n<0 ? -n : n;

}

double abs(double n) {

 cout << "In double abs()\n";
 return n<0 ? -n : n;

}

 </source>

Overload function: int and float

<source lang="cpp">

1. include <iostream>

using namespace std; int difference(int a, int b) {

 return a-b;

} float difference(float a, float b) {

 return a-b;

} int main() {

 int (*p1)(int, int);
 float (*p2)(float, float);
 p1 = difference; // address of difference(int, int)
 p2 = difference; // address of difference(float, float);
 cout << p1(10, 5) << " ";
 cout << p2(10.5, 8.9) << "\n";
 return 0;

}

 </source>

Overload function: int and long

<source lang="cpp">

1. include <iostream>

using namespace std; int rotate(int i); long rotate(long i); int main() {

 int a;
 long b;
 a = 0x8000;
 b = 8;
 cout  << rotate(a);
 cout << endl;
 cout << rotate(b);
 
 return 0;

} int rotate(int i) {

 int x;

 if(i & 0x8000) x = 1;
 else x = 0;
 i = i << 1;
 i += x;
 return i;

} long rotate(long i) {

 int x;

 if(i & 0x80000000) x = 1;
 else x = 0;
 i = i << 1;
 i += x;
 return i;

}

 </source>

Overload function to accept integer or char * argument

<source lang="cpp">

1. include <iostream>

using namespace std; void sleep(int n); void sleep(char *n);

1. define DELAY 100000

int main() {

 cout << ".";
 sleep(3);
 cout << ".";
 sleep("2");
 cout << ".";
 return 0;

} // Sleep() with integer argument. void sleep(int n) {

 long i;
 for( ; n; n--)
   for(i = 0; i <DELAY; i++) ;

} // Sleep() with char * argument. void sleep(char *n) {

 long i;
 int j;
 j = atoi(n);
 for( ; j; j--)
   for(i = 0; i <DELAY; i++) ;

}

 </source>

Overload the min() function.

<source lang="cpp">

1. include <iostream>
2. include <cctype>

using namespace std; char min(char a, char b); int min(int a, int b); double min(double a, double b); int main() {

 cout << "Min is: " << min("x", "a") << endl;
 cout << "Min is: " << min(10, 20) << endl;
 cout << "Min is: " << min(0.2234, 99.2) << endl;
 return 0;

} // min() for chars char min(char a, char b) {

 return tolower(a)<tolower(b) ? a : b;

} // min() for ints int min(int a, int b) {

 return a<b ? a : b;

} // min() for doubles double min(double a, double b) {

 return a<b ? a : b;

}

 </source>