\sqrt{\left(\left(\frac{\left(a + b\right) + c}{2} \cdot \left(\frac{\left(a + b\right) + c}{2} - a\right)\right) \cdot \left(\frac{\left(a + b\right) + c}{2} - b\right)\right) \cdot \left(\frac{\left(a + b\right) + c}{2} - c\right)}double f(double a, double b, double c) {
double r87101 = a;
double r87102 = b;
double r87103 = r87101 + r87102;
double r87104 = c;
double r87105 = r87103 + r87104;
double r87106 = 2.0;
double r87107 = r87105 / r87106;
double r87108 = r87107 - r87101;
double r87109 = r87107 * r87108;
double r87110 = r87107 - r87102;
double r87111 = r87109 * r87110;
double r87112 = r87107 - r87104;
double r87113 = r87111 * r87112;
double r87114 = sqrt(r87113);
return r87114;
}