/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
 
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		List<Integer> routeLine = new ArrayList<Integer>();
		routeLine.add(0);
		routeLine.add(1);
		routeLine.add(2);
		routeLine.add(3);
		routeLine.add(4);
		routeLine.add(5);
 
		String result = Arrays.toString(routeLine.subList(4,6).toArray());
 
		//Baidu
		// result = String.valueOf(gps2d(24.189407,120.710013,24.189367,120.71));
		// result = String.valueOf(gps2d(24.189407,120.710013,24.188386,120.710014));
		//Google
		result = String.valueOf(gps2d(6.059924, 125.417117,-35.954718, 85.338992));
 
		System.out.println(result);
	}
 
	private static double gps2d(double lat_a, double lng_a, double lat_b, double lng_b) {
		double d = 0;
		lat_a=lat_a*Math.PI/180;
		lng_a=lng_a*Math.PI/180;
		lat_b=lat_b*Math.PI/180;
		lng_b=lng_b*Math.PI/180;
 
		d=Math.sin(lat_a)*Math.sin(lat_b)+Math.cos(lat_a)*Math.cos(lat_b)*Math.cos(lng_b-lng_a);
		d=Math.sqrt(1-d*d);
		d=Math.cos(lat_b)*Math.sin(lng_b-lng_a)/d;
		d=Math.asin(d)*180/Math.PI;
 
		if (lat_b >= lat_a) {
            if (d < 0) {
                d = 360 + d;
            }
        } else {
            d = 180 - d;
        }
 
		// d = Math.round(d*10000);
		return d;
	}
}

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