Alright folks, let me tell you about my little adventure with the Josephus problem. I stumbled upon this thing and thought, “Hey, that looks like a fun brain teaser!” So, I dove right in.

First thing I did was try to understand the problem. You know, the whole ring of people, counting off, and eliminating every kth person until only one is left. Sounded simple enough, but I knew it would get tricky fast. I started by sketching it out on paper, drawing little circles to represent people and crossing them out as I “eliminated” them. Old school, I know, but it helped me visualize the process.
Then, I tried to come up with a straightforward solution. I initially thought, “Okay, let’s just use an array (or a list, depending on your poison) to represent the people. We’ll go through the array, counting, and when we hit ‘k’, we remove that element.” Seemed legit, right? Well, it worked for small cases, but it was SLOW. Like, glacial slow, especially when the number of people got bigger. Removing elements from the middle of an array repeatedly is a killer on performance.
So, I scratched my head and thought, “There HAS to be a better way.” I started googling around, looking for clues. That’s when I discovered the mathematical formula for solving the Josephus problem. It involves some modular arithmetic and bit manipulation. I won’t lie, it took me a minute to wrap my head around it. But once I did, I felt like I’d unlocked some secret code.
I implemented the formula in code, and BAM! It was lightning fast. I could solve the problem for thousands, even millions, of people in the blink of an eye. It was so satisfying to see that mathematical elegance translated into efficient code.
But I wasn’t done yet. I wanted to understand WHY the formula worked. So, I spent some time tracing the logic, working through examples by hand, and trying to understand the underlying pattern. It’s one thing to use a formula, but it’s another to truly grasp the reasoning behind it.

I also experimented with different data structures. Instead of an array, I tried using a linked list. It’s a bit more complex to implement, but removing elements from a linked list is much faster than removing them from an array. The linked list approach was still slower than the mathematical formula, but it was a good exercise in understanding different trade-offs in data structures.
Here’s what I learned from this little Josephus adventure:
- Don’t be afraid to start with a simple, brute-force solution. It can help you understand the problem better.
- There’s often a mathematical solution to programming problems. Google is your friend!
- Understanding WHY a solution works is just as important as implementing it.
- Experiment with different data structures and algorithms to find the most efficient solution.
Overall, it was a fun and educational experience. The Josephus problem is a great example of how a seemingly simple problem can have a surprisingly elegant solution. Plus, it gave me a chance to dust off my math skills. Definitely a win-win!