扩展PHP：超文本处理器[关闭]

Question

I am learning recursion now in my programming class, and while I understand how to use recursion for things like factorials and backtracking algorithms, I've been trying to wrap my head around how a recursive acronym, such as PHP, would be iterated for quite some time know. How could one write a program to iterate the expansion of PHP n times?

EDIT: I need to clarify my question PHP is a recursive acronym, stands for PHP: Personal home page. So if you were to expand PHP: Hypertext processor an infinite number of times, would it look like PHP:Hypertext Processor Hypertext processor hypertext processor... or soemthing different

Answer 1

I am completely guessing as to what you're asking, but if I'm right it would be something like this:

function recursePHP($n) {
    if ($n <= 0)
        return 'PHP';

    return recursePHP($n-1) . 'Hypertext Processor';
}

This is taking a recursive function approach to your question that would spit out, given n=2: "PHP Hypertext Processor Hypertext Processor"

I see this as the correct way to recurse through the acronym, as thinking about the first iteration you end up with "PHP Hypertext Processor", the PHP in this resolves to "PHP Hypertext Processor" so that becomes "PHP Hypertext Processor Hypertext Processor" with the bold section being the PHP in the first iteration, etc. Until you've iterated through the specified number of recursions then you don't resolve PHP and end up with PHP at the beginning followed by n "Hypertext Processor"s.