double f(double c_p, double c_n, double t, double s) {
double r125991 = 1.0;
double r125992 = s;
double r125993 = -r125992;
double r125994 = exp(r125993);
double r125995 = r125991 + r125994;
double r125996 = r125991 / r125995;
double r125997 = c_p;
double r125998 = pow(r125996, r125997);
double r125999 = r125991 - r125996;
double r126000 = c_n;
double r126001 = pow(r125999, r126000);
double r126002 = r125998 * r126001;
double r126003 = t;
double r126004 = -r126003;
double r126005 = exp(r126004);
double r126006 = r125991 + r126005;
double r126007 = r125991 / r126006;
double r126008 = pow(r126007, r125997);
double r126009 = r125991 - r126007;
double r126010 = pow(r126009, r126000);
double r126011 = r126008 * r126010;
double r126012 = r126002 / r126011;
return r126012;
}