Leetcode 1344: Angle between hands of a clock

In this Leetcode problem, we look to find the angle between the minute and the hour of a clock.

Problem statement

In that case, this is more a Math than computer science problem. So let’s put our geometry hat and calculate the angle between the origin and the hour hand:

hour angle:
alpha = (minutes spent) * 360.0 / (total minutes for full circle) 
      = ((hour * 60) + minutes) * 360.0 / 12 * 60
      = ((hour * 60) + minutes) / 2.0
Result is (% 360.0) since the number of hours can be 12+ and we want an angle between 0 and 360.

Then the minutes angle:

minutes angle:
beta = minutes * 360.0 / (total minutes for full circle)
     = minutes * 360.0 / 60.0
     = minutes * 6.0

Then the (positive) angle formed by the 2 hands is:

angle = Math.abs(beta — alpha)

Then, of course, we need to calculate the other positive angle to get from one hand to the other, then:

result = Math.min(angle, 360.0 - angle)

Here is the code, making the calculations I detailed above:

class Solution {
    public double angleClock(int hour, int minutes) {
        double alpha = ((hour * 60  + minutes) / 2.0) % 360.0;
        double beta…