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

double f(double pre_s, int stt, int stop, double *re_s) {
  int i;
  double s;
  s = pre_s;
  for (i = stt; i <= stop; i++)
    s += (1.0 / i);
  *re_s = s;
  return s / log(stop);
}

#define N 8
int main() {
  int i, p1, p2;
  double s;
  s = 0.0;
  for (i = 0, p1 = 1, p2 = 10; i < N; i++, p1 = p2, p2 *= 10)
    printf("%d, %f\n", p2, f(s, p1, p2, &s)); fflush(stdout);
  return 0;
}
/* end */