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#include<bits/stdc++.h>
#define re register
typedef long long ll;
template<class T>
inline void read(T &x)
{
x=0;
char ch=getchar(),t=0;
while(ch<'0'||ch>'9') t|=ch=='-',ch=getchar();
while(ch>='0'&&ch<='9') x=(x<<3)+(x<<1)+(ch^48),ch=getchar();
if(t) x=-x;
}
template<class T,class ...T1>
inline void read(T &x,T1 &...x1){ read(x),read(x1...); }
template<class T>
inline void write(T x)
{
if(x<0) putchar('-'),x=-x;
if(x>9) write(x/10);
putchar(x%10+'0');
}
template<>
inline void write(bool x){ putchar(x?'1':'0'); }
template<>
inline void write(char c){ putchar(c); }
template<>
inline void write(char *s){ while(*s!='\0') putchar(*s++); }
template<>
inline void write(const char *s){ while(*s!='\0') putchar(*s++); }
template<class T,class ...T1>
inline void write(T x,T1 ...x1){ write(x),write(x1...); }
template<class T>
inline bool checkMax(T &x,T y){ return x<y?x=y,1:0; }
template<class T>
inline bool checkMin(T &x,T y){ return x>y?x=y,1:0; }
const int MAXN=2e5+10;
const int INF=0x3f3f3f3f;
int N;
struct Point
{
double x,y;
bool operator<(const Point &a) const
{ return x==a.x?y<a.y:x<a.x; }
}Pt[MAXN],a[MAXN],b[MAXN];
inline double getDist(int x,int y)
{ return std::sqrt((Pt[x].x-Pt[y].x)*(Pt[x].x-Pt[y].x)+(Pt[x].y-Pt[y].y)*(Pt[x].y-Pt[y].y)); }
inline double getDist(Point x,Point y)
{ return std::sqrt((x.x-y.x)*(x.x-y.x)+(x.y-y.y)*(x.y-y.y)); }
double solve(int l,int r)
{
if(l>=r) return INF;
int mid=(l+r)>>1;
double dx=(Pt[mid].x+Pt[mid+1].x)/2.0;
double res=std::min(solve(l,mid),solve(mid+1,r));
int l1=l,r1=mid+1,cnt=0;
for(int i=l;i<=r;++i)
{
if(l1<=mid&&(r1>r||Pt[l1].y<Pt[r1].y))
{
a[i]=Pt[l1++];
if(dx-res/2<a[i].x) b[++cnt]=a[i];
}
else
{
a[i]=Pt[r1++];
if(a[i].x<dx+res/2) b[++cnt]=a[i];
}
}
for(int i=l;i<=r;++i) Pt[i]=a[i];
for(int i=1;i<=cnt;++i)
for(int j=i+1;j<=cnt;++j)
{
if(b[j].y-b[i].y>=res/2) break;
for(int k=j+1;k<=cnt;++k)
{
if(b[k].y-b[j].y>=res/2) break;
checkMin(res,getDist(b[i],b[j])+getDist(b[i],b[k])+getDist(b[j],b[k]));
}
}
return res;
}
int main()
{
read(N);
for(int i=1;i<=N;++i) scanf("%lf%lf",&Pt[i].x,&Pt[i].y);
std::sort(Pt+1,Pt+N+1);
printf("%.6lf",solve(1,N));
return 0;
}
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