double f(double c_p, double c_n, double t, double s) {
double r21702766 = 1.0;
double r21702767 = s;
double r21702768 = -r21702767;
double r21702769 = exp(r21702768);
double r21702770 = r21702766 + r21702769;
double r21702771 = r21702766 / r21702770;
double r21702772 = c_p;
double r21702773 = pow(r21702771, r21702772);
double r21702774 = r21702766 - r21702771;
double r21702775 = c_n;
double r21702776 = pow(r21702774, r21702775);
double r21702777 = r21702773 * r21702776;
double r21702778 = t;
double r21702779 = -r21702778;
double r21702780 = exp(r21702779);
double r21702781 = r21702766 + r21702780;
double r21702782 = r21702766 / r21702781;
double r21702783 = pow(r21702782, r21702772);
double r21702784 = r21702766 - r21702782;
double r21702785 = pow(r21702784, r21702775);
double r21702786 = r21702783 * r21702785;
double r21702787 = r21702777 / r21702786;
return r21702787;
}