Especially to Burunduk1 :-)

How your output method is organized?
I tried different ideas. My best time is 0.078.
My algo is O( n log n ).

Maybe anyone have any ideas?

Thanks. Bye.

Mine one is also O(nlogn)
But its constant is very small.

About output:

/* printf("%d\n", mi); */

char s[9];
int l = 0;
while (mi)
  s[l++] = mi % 10, mi /= 10;
while (l--)
  putc('0' + s[l], stdout);
putc('\n', stdout);

Thanks. I improved my algo, now 0.062
Does your structure use binary operations intensively?