Program to calculate the area of a triangle

#include<iostream.h>
#include<conio.h>
#include<math.h>
void main()
{
  clrscr();
  float a,b,c,s,area;
  cout<<"Enter the 3 sides : ";
  cin>>a>>b>>c;
  s=a+b+c;
  area=sqrt(s*(s-a)*(s-b)*(s-c));
  cout<<"Area :"<<area;
  getch();
}