\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 r21955 = a;
double r21956 = b;
double r21957 = r21955 + r21956;
double r21958 = c;
double r21959 = r21957 + r21958;
double r21960 = 2.0;
double r21961 = r21959 / r21960;
double r21962 = r21961 - r21955;
double r21963 = r21961 * r21962;
double r21964 = r21961 - r21956;
double r21965 = r21963 * r21964;
double r21966 = r21961 - r21958;
double r21967 = r21965 * r21966;
double r21968 = sqrt(r21967);
return r21968;
}