My approach to the classic PHP beer challenge interview
When I walked into my second-round interview for a senior web developer position at Supreme Optimization company, I never expected to encounter the classic “99 Bottles of beer on the wall” song challenge. But there I was, staring at what seemed like a simple task that would test my PHP skills in ways I hadn’t anticipated.
The PHP beer challenge looked straightforward on paper, but I quickly realized it was designed to reveal how I approach problem-solving under pressure.
How I broke down the requirements?
My first step was analyzing exactly what the interviewer wanted. I needed to create a program that counts down from 99 bottles of beer to zero, handling grammar correctly and formatting the output properly.
I identified the core challenges:
- Implementing a countdown loop from 99 to 0
- Managing singular vs plural bottle text
- Formatting each verse correctly
- Handling the transition to “no more bottles”
Rather than jumping straight into coding, I spent a few minutes planning my approach. This proved crucial for completing the PHP beer challenge within my 20-minute timeframe.
How I solved the challenge?
I decided to keep things simple. My experience has taught me that overcomplicating interview problems usually backfires. I chose to create two focused functions that would handle the main logic cleanly.
First, I wrote a helper function for the grammar issue:
function getBottleText($count) {
return $count === 1 ? 'bottle' : 'bottles';
}This solved the singular/plural problem elegantly. I could call this function with any number and get grammatically correct text every time.
Next, I created the verse printing function:
function printVerse($i) {
$bottle = getBottleText($i);
$next = $i - 1;
$nextBottle = getBottleText($next);
echo "$i $bottle of beer on the wall, $i $bottle of beer\n";
if ($next > 0) {
echo "Take one down and pass it around, $next $nextBottle of beer on the wall\n\n";
} else {
echo "Take one down and pass it around, no more bottles of beer on the wall\n\n";
}
}Why I chose this implementation approach?
My main loop was straightforward, a simple for loop counting backwards:
for ($i = 99; $i > 0; $i--) {
printVerse($i);
}I finished with the traditional ending verse that suggests going to the store for more beer.
echo "No more bottles of beer on the wall, no more bottles of beer\n";
echo "Go to the store and buy some more, 99 bottles of beer on the wall\n";I chose this approach because it prioritized readability and maintainability. During interviews, I’ve learned that demonstrating clean coding practices often matters more than showing off complex algorithms.
Handling edge cases in my solution
The trickiest part of the PHP beer challenge was managing the transition from “1 bottle” to “no more bottles.” My conditional logic in the printVerse() function handled this seamlessly.
I also made sure to include the proper spacing and formatting that makes the output look exactly like the traditional song lyrics. These details show attention to requirements, which interviewers always appreciate.
What I learned from this coding challenge
Completing this PHP beer challenge in just 20 minutes taught me several valuable lessons about interview preparation and problem-solving approach.
First, I confirmed that simple solutions often work best. My initial instinct was to create classes and implement design patterns, but the straightforward approach proved more effective.
Second, I realized how important it is to handle edge cases gracefully. The transition from counting down to the final “no more bottles” message required careful consideration.
My recommendations for similar challenges
If you encounter the PHP beer challenge or similar problems in interviews, I recommend focusing on clarity over complexity. Write code that other developers can easily understand and maintain.
Test your edge cases mentally before writing them. In my case, thinking through what happens at bottle number 1 helped me structure the conditional logic correctly.
Don’t rush the planning phase. Those few minutes I spent analyzing the requirements saved me significant debugging time later.
Remember that interviewers want to see your thought process, not just the final code. Explaining your approach while coding demonstrates communication skills alongside technical ability.
Beyond the interview room
This PHP beer challenge experience reminded me why I love programming. Taking a seemingly simple problem and crafting an elegant solution never gets old.
The skills I used: loop logic, string formatting, and function organization, apply to countless real-world development scenarios. Inventory systems, report generation, and data processing all use similar patterns.
My 20 minute solution now serves as a reminder that sometimes the best code is the code that simply works, does what it’s supposed to do, and can be understood by the next developer who reads it.
Want to see my code or share your approach?
I’ve made my complete PHP beer challenge solution available on GitHub for anyone who wants to examine the code or learn from it. You can find the full implementation, including all the functions and logic I described, at: https://github.com/gydoar/99-Bottles-of-beer-on-the-wall
But here’s where it gets interesting, I’m curious to see how other developers would tackle this same challenge. Every programmer has their own style and approach, and I believe we can all learn from each other’s solutions.
I’m inviting you to submit your own version! Whether you prefer object-oriented approaches, functional programming, different languages, or creative optimizations, I’d love to see your take on the PHP beer challenge. Submit a pull request with your solution and let’s build a collection of different approaches to this classic problem.
Ready to show how you’d solve it? Fork the repository and submit your pull request, I’m excited to see what creative solutions the community comes up with!
Leave a Reply