#include<stdio.h>
#include<math.h>
int main(void)
{
int a,b,c;
double s,perimeter,area;
scanf("%d%d%d",&a,&b,&c);
if(a+b>c&&a+c>b&&b+c>a)
{
s=(a+b+c)/2.0;
area=sqrt(s*(s-a)*(s-b)*(s-c));
perimeter=(a+b+c);
printf("area = %0.2f; perimeter = %0.2f",area,perimeter);
}
else
printf("These sides do not correspond to a valid triangle");
return 0;
}