double f(double c_p, double c_n, double t, double s) {
double r8218956 = 1.0;
double r8218957 = s;
double r8218958 = -r8218957;
double r8218959 = exp(r8218958);
double r8218960 = r8218956 + r8218959;
double r8218961 = r8218956 / r8218960;
double r8218962 = c_p;
double r8218963 = pow(r8218961, r8218962);
double r8218964 = r8218956 - r8218961;
double r8218965 = c_n;
double r8218966 = pow(r8218964, r8218965);
double r8218967 = r8218963 * r8218966;
double r8218968 = t;
double r8218969 = -r8218968;
double r8218970 = exp(r8218969);
double r8218971 = r8218956 + r8218970;
double r8218972 = r8218956 / r8218971;
double r8218973 = pow(r8218972, r8218962);
double r8218974 = r8218956 - r8218972;
double r8218975 = pow(r8218974, r8218965);
double r8218976 = r8218973 * r8218975;
double r8218977 = r8218967 / r8218976;
return r8218977;
}