Description

Input

Output

Sample Input

Sample Output

HINT

其实这题就是一道旋转卡壳的裸题，但是我的精度萎了。直接上hzwer的代码吧。。。

#include
    
     #include
     
      #include
      
       #include
       
        #include
        
         #include
         
          #include
          
           #include
           
            #define eps 1e-8#define inf 1000000000using namespace std;double ans=1e60;int n,top;struct P{ double x,y; P(){} P(double _x,double _y):x(_x),y(_y){} friend bool operator<(P a,P b){ return fabs(a.y-b.y)
            
             
              
               0;}void graham(){ for(int i=2;i<=n;i++) if(p[i]
               
                1&&(q[top]-q[top-1])*(p[i]-q[top])
                
                 -eps)p=(p+1)%top; while((q[i+1]-q[i])/(q[r+1]-q[i])-(q[i+1]-q[i])/(q[r]-q[i])>-eps)r=(r+1)%top; if(i==0)l=r; while((q[i+1]-q[i])/(q[l+1]-q[i])-(q[i+1]-q[i])/(q[l]-q[i])