Cod sursa(job #765583)

Utilizator BlaugranasEnal Gemaledin Blaugranas Data 8 iulie 2012 11:20:02
Problema Cele mai apropiate puncte din plan Scor 60
Compilator cpp Status done
Runda Arhiva educationala Marime 1.11 kb
#include<cstdio>
#include<cmath>
#include<algorithm>
using namespace std;
struct P
{long long x,y;};
P a[100001],b[100001],c[100001],d[100051],e;
int i,n;

int A(P a,P b)
{return a.x<b.x||(a.x==b.x&&a.y<b.y);}

long long B(P p,P q)
{return (p.x-q.x)*(p.x-q.x)+(p.y-q.y)*(p.y-q.y);}

long long D(int p,int q)
{int m=(p+q)/2,i,j,l,k;
long long r=1LL<<62;
if(q-p<=1)
       return r;
if(q-p==2)
       {if(c[p].x>c[p+1].x)
               e=c[p],c[p]=c[p+1],c[p+1]=e;
       return B(a[p],a[p+1]);}
r=min(D(p,m),D(m,q));
for(k=i=p,j=m+1;i<=m&&j<=q;)
if(c[i].x<c[j].x)
       d[k++]=c[i++];
else
       d[k++]=c[j++];
for(;i<=m;d[k++]=c[i++]);
for(;j<=q;d[k++]=c[j++]);
for(j=0,i=p;i<=q;i++)
if(abs(d[i].y-a[m].x)<=r)
       b[++j]=d[i];
for(l=1;l<j;l++)
for(k=l+1;k<=j&&k-l<8;k++)
       r=min(r,B(b[l],b[k]));
return r;}

int main()
{freopen("cmap.in","r",stdin);
freopen("cmap.out","w",stdout);
scanf("%d",&n);
for(i=1;i<=n;i++)
       scanf("%lld%lld",&a[i].x,&a[i].y);
sort(a+1,a+n+1,A);
for(i=1;i<=n;i++)
       c[i].x=a[i].y,c[i].y=a[i].x;
printf("%.6lf\n",sqrt(D(1,n)));
return 0;}