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 r452827 = x;
        double r452828 = 1.0;
        double r452829 = r452827 + r452828;
        double r452830 = sqrt(r452829);
        double r452831 = sqrt(r452827);
        double r452832 = r452830 - r452831;
        double r452833 = y;
        double r452834 = r452833 + r452828;
        double r452835 = sqrt(r452834);
        double r452836 = sqrt(r452833);
        double r452837 = r452835 - r452836;
        double r452838 = r452832 + r452837;
        double r452839 = z;
        double r452840 = r452839 + r452828;
        double r452841 = sqrt(r452840);
        double r452842 = sqrt(r452839);
        double r452843 = r452841 - r452842;
        double r452844 = r452838 + r452843;
        double r452845 = t;
        double r452846 = r452845 + r452828;
        double r452847 = sqrt(r452846);
        double r452848 = sqrt(r452845);
        double r452849 = r452847 - r452848;
        double r452850 = r452844 + r452849;
        return r452850;
}