100% area of traingle using Heron's formula

// area of triangle according to Heron's formula
#include <stdio.h>
#include<math.h>
void main()
{
  float a,b,c,s,area;
  printf("\n enter the sides of the triangle in proper units:");
  scanf("%f%f%f",&a,&b,&c);
  s=(a+b+c)/2.0; //s=semi-perimeter
  printf("area of traingle with 3 given side lengths=%f sq units",sqrt(s*(s-a)*(s-b)*(s-c)));
}// end of main
    ఔట్పుట్ తెరమీద

enter the sides of the triangle:3 4 5
area of traingle with 3 given side lengths=6.000000 sq units