double f(double c_p, double c_n, double t, double s) {
double r63913234 = 1.0;
double r63913235 = s;
double r63913236 = -r63913235;
double r63913237 = exp(r63913236);
double r63913238 = r63913234 + r63913237;
double r63913239 = r63913234 / r63913238;
double r63913240 = c_p;
double r63913241 = pow(r63913239, r63913240);
double r63913242 = r63913234 - r63913239;
double r63913243 = c_n;
double r63913244 = pow(r63913242, r63913243);
double r63913245 = r63913241 * r63913244;
double r63913246 = t;
double r63913247 = -r63913246;
double r63913248 = exp(r63913247);
double r63913249 = r63913234 + r63913248;
double r63913250 = r63913234 / r63913249;
double r63913251 = pow(r63913250, r63913240);
double r63913252 = r63913234 - r63913250;
double r63913253 = pow(r63913252, r63913243);
double r63913254 = r63913251 * r63913253;
double r63913255 = r63913245 / r63913254;
return r63913255;
}