Cod sursa(job #1364201)

Utilizator mirceadinoMircea Popoveniuc mirceadino Data 27 februarie 2015 15:41:49
Problema Cele mai apropiate puncte din plan Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.39 kb
#include<cstdio>
#include<string>
#include<set>
#include<algorithm>
#include<cmath>

using namespace std;

#ifdef HOME
const string inputFile = "input.txt";
const string outputFile = "output.txt";
#else
const string problemName = "cmap";
const string inputFile = problemName + ".in";
const string outputFile = problemName + ".out";
#endif

typedef pair<int, int> PII;
const int INF = (1 << 30);
const int NMAX = 100000 + 5;

struct cmp {
    bool operator()(const PII &A, const PII &B) const {
        return A.second < B.second;
    }
};

int N;
PII P[NMAX];
double sol;
set<PII, cmp> S;

double dist(PII A, PII B) {
    return sqrt((A.first - B.first) * 1LL * (A.first - B.first) + (A.second - B.second) * 1LL * (A.second - B.second));
}

int main() {
    int i, j;

    freopen(inputFile.c_str(), "r", stdin);
    freopen(outputFile.c_str(), "w", stdout);

    scanf("%d", &N);

    for(i = 1; i <= N; i++)
        scanf("%d%d", &P[i].first, &P[i].second);

    sort(P + 1, P + N + 1);
    sol = INF;

    for(i = j = 1; i <= N; i++) {
        while(j < i && P[j].first + sol < P[i].first) {
            S.erase(P[j]);
            j++;
        }

        auto p = S.lower_bound(make_pair(0, P[i].second - sol - 1));

        for(auto it = p; it != S.end() && P[i].second + sol > it->second; it++)
            sol = min(sol, dist(*it, P[i]));

        S.insert(P[i]);
    }

    printf("%.10f\n", sol);

    return 0;
}