uva 10195

#include<stdio.h>
#include<math.h>
int main()
{
    double a,b,c,s,r;
    while(scanf("%lf%lf%lf",&a,&b,&c)==3)
    {
        if(a==0||b==0||c==0)

            printf("The radious of the round table is: 0.000\n");


        else
        {
            s=(a+b+c)/2;
            r=(s-a)*(s-b)*(s-c)/s;
            r=sqrt(r);
            printf("The radious of the round table is: %.3lf\n",r);

        }

    }

    return 0;
}