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 r458472 = x;
        double r458473 = 1.0;
        double r458474 = r458472 + r458473;
        double r458475 = sqrt(r458474);
        double r458476 = sqrt(r458472);
        double r458477 = r458475 - r458476;
        double r458478 = y;
        double r458479 = r458478 + r458473;
        double r458480 = sqrt(r458479);
        double r458481 = sqrt(r458478);
        double r458482 = r458480 - r458481;
        double r458483 = r458477 + r458482;
        double r458484 = z;
        double r458485 = r458484 + r458473;
        double r458486 = sqrt(r458485);
        double r458487 = sqrt(r458484);
        double r458488 = r458486 - r458487;
        double r458489 = r458483 + r458488;
        double r458490 = t;
        double r458491 = r458490 + r458473;
        double r458492 = sqrt(r458491);
        double r458493 = sqrt(r458490);
        double r458494 = r458492 - r458493;
        double r458495 = r458489 + r458494;
        return r458495;
}