AngleBetweenHourAndMin.java

// Java program to find angle between hour and minute hands
import java.io.*;
class AngleBetweenHourAndMin
{
    // Function to calculate the angle
    static int calcAngle(double h, double m)
    {
        // validate the input
        if (h <0 || m < 0 || h >12 || m > 60)
            System.out.println("Wrong input");

        if (h == 12)
            h = 0;
        if (m == 60)
            m = 0;

        // Calculate the angles moved by hour and minute hands
        // with reference to 12:00
        int hour_angle = (int)(0.5 * (h*60 + m));
        int minute_angle = (int)(6*m);

        // Find the difference between two angles
        int angle = Math.abs(hour_angle - minute_angle);

        // smaller angle of two possible angles
        angle = Math.min(360-angle, angle);

        return angle;
    }

    // Driver program
    public static void main (String[] args)
    {
        System.out.println(calcAngle(9, 60)+" degree");
        System.out.println(calcAngle(3, 30)+" degree");
    }
}