text: #include<stdio.h>
  #include<math.h>
  double aroftri(double a,double b,double c);
  main()
  {
  	double a,b,c,area;
  	printf(" enter the sides a ,b ,c of triangle ");
  	scanf("%lf%lf%lf",&a,&b,&c);
  	area=aroftri(a,b,c);
  	printf("\narea=%lf",area);
  }
  
  double aroftri(double a,double b,double c){
  	double area=0,s=(a+b+c)/2;
  	area=sqrt(s*(s-a)*(s-b)*(s-c));
  	return (area);
  }
  
  