Programming Tutorials

Function overloading in C++

By: Babbar Ankit  

C++ permits the use of two function with the same name. However such functions essentially have different argument list. The difference can be in terms of number or type of arguments or both.

This process of using two or more functions with the same name but differing in the signature is called function overloading.

But overloading of functions with different return types are not allowed.

In overloaded functions , the function call determines which function definition will be executed.

The biggest advantage of overloading is that it helps us to perform same operations on different datatypes without  having the need to use separate names for each version.

Example

#include<iostream>
using namespace std;

int abslt(int );
long abslt(long );
float abslt(float );
double abslt(double );

int main()
{

int intgr=-5;
long lng=34225;
float flt=-5.56;
double dbl=-45.6768;
cout<<\" absoulte value of \"<<intgr<<\" = \"<<abslt(intgr)<<endl;
cout<<\" absoulte value of \"<<lng<<\" = \"<<abslt(lng)<<endl;
cout<<\" absoulte value of \"<<flt<<\" = \"<<abslt(flt)<<endl;
cout<<\" absoulte value of \"<<dbl<<\" = \"<<abslt(dbl)<<endl;
}
int abslt(int num)
{
if(num>=0)
return num;
else
 return (-num);
}
long abslt(long num)
{
if(num>=0)
return num;
else return (-num);
}
float abslt(float  num)
{
if(num>=0)
return num;
else return (-num);
}
double abslt(double  num)
{
if(num>=0)
return num;
else return (-num);
}

OUTPUT
 absoulte value of -5 = 5
 absoulte value of 34225 = 34225
 absoulte value of -5.56 = 5.56
 absoulte value of -45.6768 = 45.6768


the above function finds the absolute value of any number int, long, float ,double.

In  C, the above is implemented as a set of different function abs()-for int, fabs()-for double ,labs()-for long.

The use of overloading may not have reduced the code complexity /size but has definitely made it easier to understand and avoided the necessity of remembering different names for each version function which perform identically the same task.

Authors Url: http://www.botskool.com/programming-tutorials

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