Quick answers 1. I have no idea why. 2. I didn't see the question before but I solved it too quickly and he accused me. 3. Oops, this needs to be corrected.

Oz, Your code has some bugs... the corrected code is below: public class Clock { public static void main(String[] args) { System.err.println(getAngle(Integer.parseInt(args[0]),Integer.parseInt(args[1]))); } public static double getAngle(int hours, int mins) { double angle = Math.abs((hours * (360.0/12.0)) - ((60 - mins) / 5.0 * (360.0/12.0))); return angle % 360.0; } }

Think of it this way: First, you need to take the hour and do a modulo 12 on it, because there aren't 24 hours on a clock. Next, every minute, the minute hand moves by 6 degrees (360/60). Now, the hour hand does a complete rotation in 12 hours, that would be 30 degrees per hour (360 degrees / 12 hours) Of course, as the minute hand rotates beyond H:00, the hour hand keeps advancing, so we need to account for that. We know it takes 60 minutes for the hour hand to advance by 30 degrees, so the correction is (fraction of an hour) * 30 degrees. So the angle between 12 o'clock and the position of the hour hand (Ha) is: Hour = Hour % 12 -> handle values past noon Ha = 30*Hour -> position of the hour hand without correction Ha = Ha + (Minute / 60 * 30 degrees) -> correction for the position of the hour hand And the angle between noon and the minute hand (Ma) is: Ma = 360 degrees / 60 minutes * Minute And so the angle between the two hands is: Abs(Ha - Ma) For instance, for 14h20: Hour = 14 % 12 = 2 Ha = 30 * 2 = 60 (uncorrected) Ha = Ha + (20 / 60 * 30) = 70° Ma = 360 / 60 * 20 = 120° Angle between the two = 50° Whenever you have a problem like this one, try to draw it on the board, and pick easy values, for instance 6:30, which is obviously not 0°, but half of the angle that represents 5 minutes, and you'll end up figuring it out pretty quickly.

function getAngle($h, $m) { $ha = $h * 30 + ((int) $m / 60) * 30; $ma = $m * 6; return abs($ma - $ha); }

Is this the question asked at Google for real? It's not hard at all.

Just make sure u take account of the angle of hour hand

public class Clock { /** * @param args */ public static void main(String[] args) { System.out.println(getAngle(2,11)); } public static double getAngle(int hours, int mins) { System.out.println(hours * 30.0 + 30.0*mins/60.0); System.out.println(mins*360/60); double angle = Math.abs((hours * 30 + 30.0*mins/60.0) - (mins*360.0/60.0)); return angle; } }

Sorry Hasan, But I still don't think your code is correct. For example, if the time was 3:15, the angle should be 0 rather than 180 [ the output your code suggests. Similarly, if the time was 3:45, the angle should be 180 rather than 0 [ the output your code suggests. Why? because the question is the angle between the hour and the minute hand. I will post my solution soon. Its alot more complicated than people think!