Cod sursa(job #1758549)

Utilizator Burbon13Burbon13 Burbon13 Data 17 septembrie 2016 14:13:44
Problema Cele mai apropiate puncte din plan Scor 60
Compilator cpp Status done
Runda Arhiva educationala Marime 1.3 kb
#include <cstdio>
#include <fstream>
#include <algorithm>
#include <iomanip>
#define x first
#define y second

using namespace std;

ifstream f("cmap.in");
ofstream o("cmap.out");

const int nmx = 100002;
const double inf = 3000000000;

int n;
pair <double,double> v[nmx];

void citire()
{
    f >> n;
    for(int i = 1; i <= n; ++i)
        f >> v[i].x >> v[i].y;
}

inline double dist(const pair <double,double> p1, const pair <double,double> p2)
{
    return (p1.x - p2.x) * (p1.x - p2.x) + (p1.y - p2.y) * (p1.y - p2.y);
}

double divide(const int st, const int dr)
{
    if(dr - st + 1 > 3)
    {
        int mij = (st + dr) / 2;
        double minim = min(divide(st,mij),divide(mij+1,dr));

        int st1 = max(st-7,1), dr1 = min(dr+7,n);

        for(int i = st1; i <= dr1; ++i)
            for(int j = i + 1; j <= i + 7 && j <= dr1; ++j) // ???
                minim = min(minim,dist(v[i],v[j]));

        return minim;
    }
    else
    {
        double minim = inf;
        for(int i = st; i < dr; ++i)
            for(int j = i + 1; j <= dr; ++j)
                minim = min(minim,dist(v[i],v[j]));
        return minim;
    }
}

int main()
{
    citire();
    sort(v + 1, v + n + 1);
    o << fixed << setprecision(6) << sqrt(divide(1,n));
    return 0;
}