Cod sursa(job #2462301)

Utilizator adimiclaus15Miclaus Adrian Stefan adimiclaus15 Data 27 septembrie 2019 00:58:01
Problema Cele mai apropiate puncte din plan Scor 20
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.34 kb
#include <bits/stdc++.h>

using namespace std;
ifstream f("cmap.in");
ofstream g("cmap.out");
int n;
struct punct
{
    long long x,y;
};
punct a[100005];
bool cmpY(const punct &a, const punct &b)
{
    return a.y<b.y;
}
bool cmpX(const punct &a,const punct &b)
{
    return a.x<b.x;
}
long long dist(punct a,punct b)
{
    return (b.x-a.x)*(b.x-a.x)+(b.y-a.y)*(b.y-a.y);
}
long long cmap(int st,int dr)
{
    if(dr-st<=4)
    {
        long long sol=dist(a[st],a[st+1]);
        for(int i=st;i<=dr;i++)
        {
            for(int j=i+1;j<=dr;j++)
            {
                sol=min(sol,dist(a[i],a[j]));
            }
        }
        return sol;
    }
    int mij=(st+dr)/2;
    long long minim=min(cmap(st,mij),cmap(mij+1,dr));
    int nr=0;
    punct b[100005];
    for(int i=st;i<=dr;i++)
    {
        if(abs(a[i].x-a[mij].x)<minim)
        {
            nr++;
            b[nr]=a[i];
        }
    }
    sort(b+1,b+nr+1,cmpY);
    for(int i=1;i<=nr;i++)
    {
        for(int j=i+1;j<=i+8 && j<=nr;j++)
        {
            minim=min(minim,dist(b[i],b[j]));
        }
    }
    return minim;
}
int main()
{
    int i;
    f>>n;
    for(i=1;i<=n;i++)
    {
        f>>a[i].x>>a[i].y;
    }
    sort(a+1,a+n+1,cmpX);
    g<<fixed<<setprecision(6)<<sqrt(double(cmap(1,n)));
    return 0;
}