If you count maximum value V such that V/N is equal to X (after rounding to one fractional digit) this note may be useful:
V=floor(((X-1e-10)+0.049999999999999999999)*N);
(if X<10.0)
You should decrease X be 1e-10 because 9.9 may be equal to 9.90000000000004 or something like that.
Next 9.9+0.0499999999999999 is rounded to 9.9 and you must find the maximal real X value (real = not rounded).
The last note is that V is an integer value so you should use floor. When I found out there 3 facts I got AC.
Sorry for my poor English, I hope this hint will help somebody

Edited by author 22.10.2008 22:38