double f(double x, double y, double z, double t, double a) {
double r426959 = x;
double r426960 = y;
double r426961 = r426959 + r426960;
double r426962 = log(r426961);
double r426963 = z;
double r426964 = log(r426963);
double r426965 = r426962 + r426964;
double r426966 = t;
double r426967 = r426965 - r426966;
double r426968 = a;
double r426969 = 0.5;
double r426970 = r426968 - r426969;
double r426971 = log(r426966);
double r426972 = r426970 * r426971;
double r426973 = r426967 + r426972;
return r426973;
}