1000 => 501501000
500  => 62875500
333  => 18629685
1    => 3
3    => 30
4    => 60
But Wa#5

Edited by author 28.10.2006 17:09

The same with me: WA#5 can anybody tell me why

Did you use "long long"

Did you use "long long"?

Just use int64 instead of longint;

My solution is very short and I also get WA5, my answers are the same as those posted, can anyone give some hint ?

I got Accepted using BrutForce!!!

Already solved this problem, read the hint below :)

Edited by author 30.10.2006 21:20

Yes , me , too .
WA#5 but AC now , you should change "int n" into "long long n" .

Yup, 10x pal, you saved me from reading again and again this task and to wonder where I was wrong :)

Who can find my mistake?

[code deleted]

it passes all my tests, but it can't pass 5

Edited by moderator 29.12.2006 09:16

This is my formula
  for (int i = 0; i <= n; ++i)
    res += (i + n) * (n - i + 1) / 2 + i * (n - i + 1);

Thanks for the advice. Could you tell me what brings this change? n=10000 fits in an int, doesn't it?

Ha! Got accepted only with __int64 and not with long long... my djgpp returns a compilation error on such a line... could anybody explain me what should that be?

Edited by author 10.11.2006 01:16

This one is mine:
n*-~n*-~-~n>>1
Have fun!

Delete your AC code.

Edited by author 02.03.2008 12:53

Edited by author 02.03.2008 12:54

senks bro