ENG  RUSTimus Online Judge
Online Judge
Problems
Authors
Online contests
About Online Judge
Frequently asked questions
Site news
Webboard
Links
Problem set
Submit solution
Judge status
Guide
Register
Update your info
Authors ranklist
Current contest
Scheduled contests
Past contests
Rules
back to board

Discussion of Problem 1875. Angry Birds

What is in test №2?
Posted by IgorKoval(from Pskov) 22 Oct 2011 18:13
What is in test №2?
Re: What is in test №2?
Posted by NNSTU#2 22 Oct 2011 21:13
Try 1 1 2 2 3 3 4 4 5 5
Re: What is in test №2?
Posted by IgorKoval(from Pskov) 22 Oct 2011 22:38
""""It is guaranteed that there is no straight line containing the slingshot and more than one monkey.""""
This test is not correct. =)
Re: What is in test №2?
Posted by NNSTU#2 22 Oct 2011 23:08
You are right, sorry.
Try also 1 1 2 4 3 9 4 16 5 25
Re: What is in test №2?
Posted by IgorKoval(from Pskov) 22 Oct 2011 23:17
Try my test:

1 1
1 2
1 3
1 4
1 5
ans: 5

Test #2
1 5
2 8
3 10
4 8
5 5
ans : 2


1 1
2 4
3 9
4 8
5 5
ans : 3 !!!!!! =)
when we draw parabola y = a*x*x+b*x, be careful, this must be: a<0 and b!=0
P.S.:
hint: fabs( p[i].y - a*p[i].x*p[i].x - b*p[i].x ) <= 1e-10( don't use p[i].y = a*p[i].x*p[i].x + b*p[i].x )
Re: What is in test №2?
Posted by IgorKoval(from Pskov) 22 Oct 2011 23:18
NNSTU#2 wrote 22 October 2011 23:08
You are right, sorry.
Try also 1 1 2 4 3 9 4 16 5 25

ans: 5 =)

Thank you!!!

Edited by author 22.10.2011 23:32
Re: What is in test №2?
Posted by Vitaliy Karelin 24 Oct 2011 20:53
My solution got AC only on fabs()<=1e-8

fabs()<=1e-9 had WA#26 (!)
fabs()<=1e-7 had WA#57 (!!!)

I'm Angry very much.
Re: What is in test №2?
Posted by svr 25 Oct 2011 11:23
To avoid be angry!
How verify that big number D==0?
You may use next idea:
int p[6]={61,67,59,53,41,47};
for(i=1;i<=6;i++)
if(D%p[i-1]>0) break;
if (i>6) return true;

More rightly: We can solve problem 6 times in fields Z(61),...,Z(47)
All numbers will be not greater 100, but if in all fields D==0 then in N also D==0.

P.S. I appled this idea.
I had problems with logics but no problems with precision and
5 -is oldest WA test for me.

Edited by author 25.10.2011 13:05
Re: What is in test №2?
Posted by Georgi Chakarov 6 Nov 2011 16:55
I pass all the tests in the topic and have set the precision but still get WA#14.
Re: What is in test №2?
Posted by oops 12 Apr 2012 09:43
Last test is not correct, because of point (1,1) and (5,5) belong same line.