Function overloading program in C++

#include< iostream.h>
#include< conio.h>

int area (int a);
int area (int a, int b);
float area (float r);

void main ()
{
clrscr ();
cout< < " Area Of Square: "< < area (4);
cout< < " Area Of Rectangle: "< < area (4,4);
cout< < " Area Of Circle: "< < area (3.2);
getch();
}

int area (int a)
{
return (a*a);
}

int area (int a,int b)
{
return (a*b);
}

float area (float r)
{
return (3.14 * r * r);
}