#include "math.h"

/*
 * Integer square root.  We use Newton-Raphson iteration, with a
 *  starting point determined to be within about a factor of
 *  times-or-divided-by 2 based on a loop that counts powers of 4 and
 *  pwoers of 2 in parallel until the former exceeeds the argument.
 *
 * This does not test for negative arguments and does not work right
 *  for 0.  For the game's uses, these don't matter.
 */
int isqrt(int v)
{
 int i;
 int j;

 i = 1;
 j = 1;
 while (j < v)
  { i <<= 1;
    j <<= 2;
  }
 while ((i < j) || (i > j+1))
  { j = i;
    i = (i + (v/i)) / 2;
  }
 return(i);
}

/*
 * Just divide-and-round-up, done with integer arithmetic.
 */
unsigned int how_many(unsigned int n, unsigned int divr)
{
 return((n+divr-1)/divr);
}