#include<stdio.h>
#include<math.h>
void main()
{ float a,b,c,s,area;
  scanf("%f,%f,%f",&a,&b,&c);
  s=(a+b+c)/2;
  area=sqrt(s*(s-a)*(s-b)*(s-c));
  printf("a=%.2f,b=%.2f,c=%.2f\narea=%.2f\n",a,b,c,area);
}