mirror of
https://github.com/Kiritow/OJ-Problems-Source.git
synced 2024-03-22 13:11:29 +08:00
145 lines
3.2 KiB
C++
145 lines
3.2 KiB
C++
#include<cstdio>
|
|
#include<cstring>
|
|
#include<iostream>
|
|
#include<utility>
|
|
#include<string>
|
|
#include<set>
|
|
#include<vector>
|
|
#include<stack>
|
|
#include<algorithm>
|
|
#include<queue>
|
|
#include<cstdlib>
|
|
#include<map>
|
|
#include<cmath>
|
|
using namespace std;
|
|
#define FOR(i,a,b) for(int i(a);i<(b);i++)
|
|
#define REP(i,n) FOR(i,0,n)
|
|
#define CL(a,b) memset(a,b,sizeof(a))
|
|
const int M=200;
|
|
const int N=2000;
|
|
const double inf=1e250;
|
|
const double eps=1e-20;
|
|
const double pi=acos(-1.0);
|
|
struct point
|
|
{
|
|
double x,y;
|
|
bool operator < (const point a)const
|
|
{
|
|
if(y==a.y)
|
|
return x<a.x;
|
|
return y<a.y;
|
|
}
|
|
}p[M],stac[M];
|
|
int n,top;
|
|
int xmult(double x1,double y1,double x2,double y2)
|
|
{
|
|
return x1*y2-x2*y1;
|
|
}
|
|
int cross(point p0,point p1,point p2)
|
|
{
|
|
double x1=p1.x-p0.x,y1=p1.y-p0.y;
|
|
double x2=p2.x-p0.x,y2=p2.y-p0.y;
|
|
return xmult(x1,y1,x2,y2);
|
|
}
|
|
void covex_hull()
|
|
{
|
|
sort(p,p+n);
|
|
stac[0]=p[0];
|
|
stac[1]=p[1];
|
|
top=1;
|
|
for(int i=2;i<n;i++)
|
|
{
|
|
while(top>0 && cross(stac[top],p[i],stac[top-1])<=0)
|
|
top--;
|
|
stac[++top]=p[i];
|
|
}
|
|
int temp=top;
|
|
for(int i=n-2;i>=0;i--)
|
|
{
|
|
while(top>temp && cross(stac[top],p[i],stac[top-1])<=0)
|
|
top--;
|
|
stac[++top]=p[i];
|
|
}
|
|
--top;
|
|
}
|
|
point getpoint(double x,double y)
|
|
{
|
|
point temp;
|
|
temp.x=x;temp.y=y;
|
|
return temp;
|
|
}
|
|
double dist(point a,point b)
|
|
{
|
|
return sqrt((b.x-a.x)*(b.x-a.x)*1.0+(b.y-a.y)*(b.y-a.y));
|
|
}
|
|
double alldis(point a)
|
|
{
|
|
double dis=0;
|
|
for(int i=0;i<=top;i++)
|
|
{
|
|
dis+=dist(a,stac[i]);
|
|
}
|
|
return dis;
|
|
}
|
|
int main()
|
|
{
|
|
int T;
|
|
scanf("%d",&T);
|
|
while(T--)
|
|
{
|
|
scanf("%d",&n);
|
|
for(int i=0;i<n;i++)
|
|
scanf("%lf%lf",&p[i].x,&p[i].y);
|
|
covex_hull();
|
|
point pp=stac[0];
|
|
double ans=inf,step=100;
|
|
ans=alldis(pp);
|
|
while(step>0.2)
|
|
{
|
|
bool flag=true;
|
|
while(flag)
|
|
{
|
|
flag=false;
|
|
point qq=getpoint(pp.x,pp.y+step),tt=pp;
|
|
double temp=alldis(qq);
|
|
if(temp<ans)
|
|
{
|
|
ans=temp;
|
|
tt=qq;
|
|
flag=true;
|
|
}
|
|
qq=getpoint(pp.x,pp.y-step);
|
|
temp=alldis(qq);
|
|
if(temp<ans)
|
|
{
|
|
ans=temp;
|
|
tt=qq;
|
|
flag=true;
|
|
}
|
|
qq=getpoint(pp.x+step,pp.y);
|
|
temp=alldis(qq);
|
|
if(temp<ans)
|
|
{
|
|
ans=temp;
|
|
tt=qq;
|
|
flag=true;
|
|
}
|
|
qq=getpoint(pp.x-step,pp.y);
|
|
temp=alldis(qq);
|
|
if(temp<ans)
|
|
{
|
|
ans=temp;
|
|
tt=qq;
|
|
flag=true;
|
|
}
|
|
pp=tt;
|
|
}
|
|
step=step/2.0;
|
|
}
|
|
int dis=(int)(ans+0.5)*100/100;
|
|
printf("%d\n",dis);
|
|
if(T>0) puts("");
|
|
}
|
|
return 0;
|
|
}
|