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 r332155 = x;
        double r332156 = 1.0;
        double r332157 = r332155 + r332156;
        double r332158 = sqrt(r332157);
        double r332159 = sqrt(r332155);
        double r332160 = r332158 - r332159;
        double r332161 = y;
        double r332162 = r332161 + r332156;
        double r332163 = sqrt(r332162);
        double r332164 = sqrt(r332161);
        double r332165 = r332163 - r332164;
        double r332166 = r332160 + r332165;
        double r332167 = z;
        double r332168 = r332167 + r332156;
        double r332169 = sqrt(r332168);
        double r332170 = sqrt(r332167);
        double r332171 = r332169 - r332170;
        double r332172 = r332166 + r332171;
        double r332173 = t;
        double r332174 = r332173 + r332156;
        double r332175 = sqrt(r332174);
        double r332176 = sqrt(r332173);
        double r332177 = r332175 - r332176;
        double r332178 = r332172 + r332177;
        return r332178;
}