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 r357334 = x;
        double r357335 = 1.0;
        double r357336 = r357334 + r357335;
        double r357337 = sqrt(r357336);
        double r357338 = sqrt(r357334);
        double r357339 = r357337 - r357338;
        double r357340 = y;
        double r357341 = r357340 + r357335;
        double r357342 = sqrt(r357341);
        double r357343 = sqrt(r357340);
        double r357344 = r357342 - r357343;
        double r357345 = r357339 + r357344;
        double r357346 = z;
        double r357347 = r357346 + r357335;
        double r357348 = sqrt(r357347);
        double r357349 = sqrt(r357346);
        double r357350 = r357348 - r357349;
        double r357351 = r357345 + r357350;
        double r357352 = t;
        double r357353 = r357352 + r357335;
        double r357354 = sqrt(r357353);
        double r357355 = sqrt(r357352);
        double r357356 = r357354 - r357355;
        double r357357 = r357351 + r357356;
        return r357357;
}