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 r22158377 = x;
        double r22158378 = 1.0;
        double r22158379 = r22158377 + r22158378;
        double r22158380 = sqrt(r22158379);
        double r22158381 = sqrt(r22158377);
        double r22158382 = r22158380 - r22158381;
        double r22158383 = y;
        double r22158384 = r22158383 + r22158378;
        double r22158385 = sqrt(r22158384);
        double r22158386 = sqrt(r22158383);
        double r22158387 = r22158385 - r22158386;
        double r22158388 = r22158382 + r22158387;
        double r22158389 = z;
        double r22158390 = r22158389 + r22158378;
        double r22158391 = sqrt(r22158390);
        double r22158392 = sqrt(r22158389);
        double r22158393 = r22158391 - r22158392;
        double r22158394 = r22158388 + r22158393;
        double r22158395 = t;
        double r22158396 = r22158395 + r22158378;
        double r22158397 = sqrt(r22158396);
        double r22158398 = sqrt(r22158395);
        double r22158399 = r22158397 - r22158398;
        double r22158400 = r22158394 + r22158399;
        return r22158400;
}