Cannot sample enough valid points. (more)

\[\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)\]
\left(\left(\left(\sqrt{x + 1} - \sqrt{x}\right) + \left(\sqrt{y + 1} - \sqrt{y}\right)\right) + \left(\sqrt{z + 1} - \sqrt{z}\right)\right) + \left(\sqrt{t + 1} - \sqrt{t}\right)
double f(double x, double y, double z, double t) {
        double r499333 = x;
        double r499334 = 1.0;
        double r499335 = r499333 + r499334;
        double r499336 = sqrt(r499335);
        double r499337 = sqrt(r499333);
        double r499338 = r499336 - r499337;
        double r499339 = y;
        double r499340 = r499339 + r499334;
        double r499341 = sqrt(r499340);
        double r499342 = sqrt(r499339);
        double r499343 = r499341 - r499342;
        double r499344 = r499338 + r499343;
        double r499345 = z;
        double r499346 = r499345 + r499334;
        double r499347 = sqrt(r499346);
        double r499348 = sqrt(r499345);
        double r499349 = r499347 - r499348;
        double r499350 = r499344 + r499349;
        double r499351 = t;
        double r499352 = r499351 + r499334;
        double r499353 = sqrt(r499352);
        double r499354 = sqrt(r499351);
        double r499355 = r499353 - r499354;
        double r499356 = r499350 + r499355;
        return r499356;
}