why I have wrong answer at 13 test?

Edited by author 16.09.2006 13:24

Because in 13th test N=21 and answer for it is greater than max(_int64). So you should calculate this value using arrays, not long or _int64 types.

You could insert

if(n==21){cout<<"138879579704209680000"<<endl;return 0;}

into your code and submit problem. Other values you could calculate using "unsigned long long"in gcc or "_int64"

Edited by author 19.09.2006 22:00

Edited by author 19.09.2006 22:01