#include<math.h>
#include<stdio.h>
#include<assert.h>

int main() {
  double a = (pow((7.0/3), 0.5) + (1.0/3)*pow(3,0.5));

  printf("a = %f\n", a);
  a = a * a;
  printf("a = %f\n", a);
  a = (-2.0/9) * (a + (-27.0 / 2));
  printf("a = %f\n", a);
  a = pow(a, 0.5);
  printf("a = %f\n", a);
  assert(a >= 0);
}