Distance bwt two point with precision

import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

public class Solution {
    public static void main(String args[] ) throws Exception {
        /* Enter your code here. Read input from STDIN. Print output to STDOUT */
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        String line = br.readLine();
        result(line);
    }
    
    public static void result(String str) {
        //System.out.println(str);
        String[] splitStr = str.split("\\s+");
        //System.out.println("string"+splitStr[0]);
        Integer x1 = Integer.parseInt(splitStr[0]);
        Integer y1 = Integer.parseInt(splitStr[1]);
        Integer x2 = Integer.parseInt(splitStr[2]);
        Integer y2 = Integer.parseInt(splitStr[3]);
        double res = Math.sqrt((y2 - y1) * (y2 - y1) + (x2 - x1) * (x2 - x1));
        DecimalFormat f = new DecimalFormat("##.000");
        System.out.println(f.format(res));
    }
}