Throwback Sunday: Looking back at "Adapting in_between() for Binary Search Trees"

Alex makes a good point about art and programming in her SLOG. I couldn't agree more with her. Programming can be a tricky mistress sometimes, yet always creative and fun. This last semester I have had some experience helping my wife with her Art & Code projects and, though Java is not my area of expertise, I did learn a lot about what programming can do for the arts. Moreover, being creative can lead you to new ways to solve old problems. Hence, we will look back at one of the problems seen previously, Adapting in_between() for Binary Search Trees, and see how new ideas on recursiveness could shape a new answer to this question, namely Easy Recursion.

Since adapting some code by adding new lines is hardly groundbreaking, let's come back with a new solution involving our triad of One Function, One Helper and One Global Variable. The question was how to look for values inside a BST that satisfies a group of parameters (ie range of numbers, multiple of 3). This can be done rather easily with the triad. Take a look at the code below:

_gather_values = []

def in_between(node, start, end):

    _gather_values.clear()
    
    _get_values(node, start, end)
    
    return _gather_values


def _get_values(node, start, end):
    
    if node.data > start and node.data < end and node.data % 3 == 0:
        _gather_values.append(node.data)
        
    if len(node.children) != 0:
        for x in node.left:
            _get_values(x, start, end)
        for y in node.right:
            _get_values(y, start, end)
    

Now, it does have a major flaw: it does not take advantage, nor tries to take advantage of, the properties of BSTs. The code at the end of the helper function could be changed to cover the properties of BSTs (left branch goes down, right branch goes up in value). Regardless, this could be improved quickly. The point was to show that this code, which solves the problem, could be constructed easily.

Looking back at that old post, I can see how many different ways you can solve a problem. Creatively, or not, it is always exciting. Whilst I aim for writing elegant code, this does not negate the power of quick, easy solutions. Let us keep coming with creative solutions, and improve upon our code writing.