Given a time in HH:MM:SS, find the angles made by the hour and minute hands, and the minutes and seconds hands.

ClockAngle.java

import java.util.Scanner;

class ClockAngle {
	// For hour
	// 360* -> 12 hours or 12*60 minutes
	// 0.5* -> 1 minute
	// Angle wrt 00:00 = 0.5 * (60H + M)

	// For Minute
	// 360* -> 60 minutes
	// 6* -> 1 minute
	// Angle wrt 00:00 = 6M

	// Angle in between hour and minute hands 
	// |0.5 * (60H + M) - 6M|
	// If value is greater than 180, return 360-ans
	static double getAngleBetweenHourAndMinute(int hour, int min) {
		double ans = Math.abs(0.5 * (60 * hour + min) - (6 * min));
		return ans > 180 ? 360-ans : ans;
	}


	// For Minute
	// 360* -> 60 minutes or 60*60 seconds
	// 0.1* -> 1 second 
	// Angle wrt 00:00:00 = 0.1 * (60M + S)

	// For Second
	// 360* -> 60 seconds
	// 6* -> 1 second
	// Angle wrt 00:00:00 = 6S

	// Angle in betwen minute and seconds hands
	// |0.1 * (60M + S) - 6S|
	// If value is greater than 180, return 360-ans
	static double getAngleBetweenMinuteAndSecond(int min, int sec) {
		double ans = Math.abs(0.1 * (60 * min + sec) - (6 * sec));
		return ans > 180 ? 360 - ans : ans;
	}

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String[] time = sc.next().split(":");
		int hour = Integer.parseInt(time[0]);
		int min = Integer.parseInt(time[1]);
		int sec = Integer.parseInt(time[2]);

		System.out.printf("The angle made between the hour and minutes hand is %.2f.\n", getAngleBetweenHourAndMinute(hour, min));
		System.out.printf("The angle made between the minutes and seconds hand is %.2f.\n", getAngleBetweenMinuteAndSecond(min, sec));
	}
}