import java.applet.Applet;
import java.awt.*;

public class Kadai9_1 extends Applet implements Runnable {

final static double XMIN = -5.0, XMAX=5.0, YMIN=-5.0, YMAX=5.0;

int transX(double x) {
return (int)((x-XMIN)/(XMAX - XMIN)*getSize().width);
}
int transY(double y) {
return (int)((YMAX-y)/(YMAX - YMIN)*getSize().height);
}
double f1(double t, double vx, double x, double vy, double y) {
return vx;
}
double f2(double t, double vx, double x, double vy, double y) {
return -G*M*x/Math.pow(x*x+y*y,3/2);
}
double f3(double t, double vx, double x, double vy, double y) {
return vy;
}
double f4(double t, double vx, double x, double vy, double y) {
return -G*M*y/Math.pow(x*x+y*y,3/2);
}

Thread th = null;

double G=1, M=1;
double vx = 50, x = 5, vy = 50, y = 5;