W3School TIY Editor

public class Main { public static void main(String[] args) { System.out.println(Math.atan2(0.5, 0.5)); System.out.println(Math.atan2(-0.5, -0.5)); System.out.println(Math.atan2(5, 5)); System.out.println(Math.atan2(10, 20)); System.out.println(Math.atan2(-5, -5)); System.out.println(Math.atan2(-10, 10)); } }