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 r350152 = x;
        double r350153 = 1.0;
        double r350154 = r350152 + r350153;
        double r350155 = sqrt(r350154);
        double r350156 = sqrt(r350152);
        double r350157 = r350155 - r350156;
        double r350158 = y;
        double r350159 = r350158 + r350153;
        double r350160 = sqrt(r350159);
        double r350161 = sqrt(r350158);
        double r350162 = r350160 - r350161;
        double r350163 = r350157 + r350162;
        double r350164 = z;
        double r350165 = r350164 + r350153;
        double r350166 = sqrt(r350165);
        double r350167 = sqrt(r350164);
        double r350168 = r350166 - r350167;
        double r350169 = r350163 + r350168;
        double r350170 = t;
        double r350171 = r350170 + r350153;
        double r350172 = sqrt(r350171);
        double r350173 = sqrt(r350170);
        double r350174 = r350172 - r350173;
        double r350175 = r350169 + r350174;
        return r350175;
}