Wrong Anser 7 test

what a question haha. just read the question carefully

I originally read the problem statement as stating that the radius could only be up to 1000 in length. Hence, I was really confused when everyone was saying the problem was really easy. But that nightmare is behind me now.

I never figured out how to do it with that kind of restriction of the radius in under 1 second. What would be the optimal algorithm to use for that case?

The statement describes the precision as 10^-9, but in the second example I see "1.41421356237309" This number has 14 digits behind decimal point. I tried submitting answers with precision 9, 14 and 16. They all WA#1 even though my calculations have to be correct. Does someone know what's the correct precision?

Edited by author 14.04.2016 15:20

Edited by author 14.04.2016 15:20

Sandro't have anywhere to teleport him to stay in the point (0;0). Simply calculate the distance of most distant demon!

#include<iostream>
#include<cmath>
#include<iomanip>
#include<vector>
using namespace std;
struct p
{
      double rec1;
     double rec2;
};
int main()
{
    vector<int> v;
    int n;
    cin>>n;
    if(1<=n&&n<=100)
    {
        int *ptr=new int[n*2];
        for(int i=0;i<(n*2);i++)
            cin>>ptr[i];
        if(n==1)
        {
            if(ptr[0]==0)
                cout<<ptr[0]+1<<" "<<ptr[1]<<" "<<1;
            else
            cout<<ptr[0]-1<<" "<<ptr[1]<<" "<<1;
        system("pause");
            return 0;
        }
            int lessx=0,highx=0,lessy=1,highy=1;
        for(int i=2;i<(n*2);i+=2)
        {
            if(ptr[i]<ptr[lessx])
                lessx=i;
            if(ptr[i]>ptr[highx])
            highx=i;
            if(ptr[i+1]<ptr[lessy])
                lessy=i+1;
            if(ptr[i+1]>ptr[highy])
            {

                v.clear();
                highy=i+1;
                v.push_back(i+1);
            }
            else if(ptr[i+1]==ptr[highy])
                v.push_back(i+1);



            }

        int point[2];
        point[0]=(ptr[lessx]+ptr[highx])/2.0;
        point[1]=(ptr[lessy]+ptr[highy])/2.0;
        for(int i=0;i<(n*2);i=i+2)
        {
            if(ptr[i]==point[0])
            {
                if(ptr[i+1]==point[1])
                {
                point[1]++;

                }
            }
        }

        cout<<point[0]<<" "<<point[1]<<" ";
        int p1,p2,max,min;
        if(v.size()>=2)
        {
         p1=highy;max=v[0]-1;p2=highy;min=v[0]-1;
        for(int i=1;i<v.size();i++)
        {
            if(ptr[v[i]-1]>point[0])
            {
                if(ptr[v[i]-1]>ptr[max])
                    p1=v[i];
            }
            else if(ptr[v[i]-1]<ptr[min])
                p2=v[i];
        }
        }
        int highp_y[2];
        if(v.size()>=2)
   {
        if((ptr[p1-1]-point[0])>(point[0]-ptr[p2-1]))
        {
            highp_y[0]=ptr[p1-1];
            highp_y[1]=ptr[p1];
        }
        else
        {
            highp_y[0]=ptr[p2-1];
            highp_y[1]=ptr[p2];
        }
    }
        else
        {
            highp_y[0]=ptr[highy-1];
            highp_y[1]=ptr[highy];
        }



        int lessp_x[2];
        lessp_x[0]=ptr[lessx];
        lessp_x[1]=ptr[lessx+1];
    double longr[2];
        p s;
        for(int i=1;i<=2;i++)
        {
            if(i==1)
            {
                s.rec2=point[0]-lessp_x[0];
            if(lessp_x[1]>point[1])
                s.rec1=lessp_x[1]-point[1];
            else
                s.rec1=point[1]-lessp_x[1];

                longr[0]=sqrt((s.rec1*s.rec1)+(s.rec2*s.rec2));

            }
            else
            {
                s.rec1=highp_y[1]-point[1];
                if(point[0]==highp_y[0])
                {
                    longr[1]=s.rec1;
                    break;
                }
                else
                {
                    if(point[0]>highp_y[0])
                        s.rec2=point[0]-highp_y[0];
                    else
                        s.rec2=highp_y[0]-point[0];
                    longr[1]=sqrt((s.rec1*s.rec1)+(s.rec2*s.rec2));
                }
            }
        }
        cout<<fixed<<setprecision(9);
        if(longr[0]>longr[1])
            cout<<longr[0];
        else
            cout<<longr[1];

        system("pause");
return 0;

    }
    system("pause");
return 0;

    }

It takes me 2 hours.

Algo: x,y - the coordinates of a point Sandro. Use random values like this x = 0.666, y = 0.666. Radius of the circle = max distance to the enemy point.

Good Luck!
Sory for my english.

Use print '%.16f' % (result)
instead of print result

I've got WA on test 4. People who had WA on this test too, what did you fix? I use 2 ternary searchs.

Edited by author 29.10.2011 10:37

Edited by author 29.10.2011 10:37

The answers of the tests aren't unique. For example for the first sample test my AC program outputs 4.564191068 4.136298156 5.377150309. It can be also 0 0 (and the respective radius). But don't forget to check if the coordinates of your answer don't coincide with some from the input.

In the first sample
7
1 1
1 5
3 6
5 3
8 0
9 5
5 9
Result: 5 4 5
Why not 0 0 sqrt(5^2 + 9^2) or another points?
How to determine unique answer?

Edited by author 24.09.2011 11:09

Edited by author 24.09.2011 11:10

I calculated points in double.
I made all comparings with abs(a-b)<eps;
But
eps = 10^-9. - AC
eps = 10^-8. - AC
eps = 10^-7. - AC
eps = 10^-6. - AC
eps = 10^-5. - AC
eps = 10^-4. - AC
eps = 10^-3. - AC
eps = 10^-2. - AC
eps = 10^-1. - AC
eps = 10^1. - AC
eps = 10^2. - AC
eps = 10^3. - AC!!!!
eps = 10^4. - WA1.
So... I do not know much about contests rules, but it seemes strange for me)

RT~~

A simple problem , think carefully~

I don't how to slove this problem.who can help me?

What is the test 25?

I've already solved the problem, but I want know why my first solution is wrong...

#include<iostream>
#include<algorithm>
#include <list>
#include <math.h>
#include <iomanip>
using namespace std;
/*CODE*/

int main()
{
   /*CODE*/
    cout<<setprecision(9)<<fixed<</*CODE*/
    <<sqrt(r2);
return 0;
}

I can't understand the problem.
Help me,thanks.