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 r356306 = x;
        double r356307 = 1.0;
        double r356308 = r356306 + r356307;
        double r356309 = sqrt(r356308);
        double r356310 = sqrt(r356306);
        double r356311 = r356309 - r356310;
        double r356312 = y;
        double r356313 = r356312 + r356307;
        double r356314 = sqrt(r356313);
        double r356315 = sqrt(r356312);
        double r356316 = r356314 - r356315;
        double r356317 = r356311 + r356316;
        double r356318 = z;
        double r356319 = r356318 + r356307;
        double r356320 = sqrt(r356319);
        double r356321 = sqrt(r356318);
        double r356322 = r356320 - r356321;
        double r356323 = r356317 + r356322;
        double r356324 = t;
        double r356325 = r356324 + r356307;
        double r356326 = sqrt(r356325);
        double r356327 = sqrt(r356324);
        double r356328 = r356326 - r356327;
        double r356329 = r356323 + r356328;
        return r356329;
}