(SPOJ) 3827 - Pontos - Solução

import java.io.*;
import java.util.*;
import java.text.DecimalFormat;  
import java.lang.Math;  

class Main {
    public static void main(String[] args) throws NumberFormatException, IOException {
        Main processando = new Main();
        processando.processa();
       
        System.exit(0);
    }
   
    void processa() throws NumberFormatException, IOException {
        String line = "";
       
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

        line = br.readLine();
        StringTokenizer tokenizer = new StringTokenizer(line);
        int pontos = Integer.parseInt(tokenizer.nextToken());
       
        int[][] coord = new int[pontos][2];
       
        for (int i = 0; i < pontos; i++) {
            line = br.readLine();
            tokenizer = new StringTokenizer(line);
            for (int j = 0; j < 2; j++) {
                coord[i][j] = Integer.parseInt(tokenizer.nextToken());
            }
        }
       
        if (pontos <= 1) {
            System.out.println("0.000");
            return;
        }
       
        long x;
        long y;
        long diagonal;
        long menorArea = 0x3f3f3f3f3f3f3f3fl;
        for (int i = 0; i < pontos; i++) {
            for (int j = i+1; j < pontos; j++) {
                x = Math.abs(coord[j][0]-coord[i][0]);
                y = Math.abs(coord[j][1]-coord[i][1]);
              
                diagonal = (x*x)+(y*y);

                if (diagonal < menorArea) {
                    menorArea = diagonal;
                }
            }
        }
       
        // Sempre usar esse Locale para imprimir
        System.out.println(String.format(new Locale("en", "US"), "%.3f", Math.sqrt(menorArea)));
                                   
        return;
    }
}