Solving FizzBuzz Problems in Python

Video Transcription

Hi, I'm Art, and I teach Python at Noble Desktop. In this video, I'll walk you through solving FizzBuzz—one of the most enduring programming challenges you're likely to encounter in technical interviews.

Before diving in, I strongly recommend reviewing my previous videos covering functions, the range() function, and the modulo operator. These foundational concepts are essential for understanding the elegant solution we're about to build.

Here's the FizzBuzz challenge: Generate numbers from 1 to 100 (inclusive) and apply the following logic to each number. If it's divisible by 3 with no remainder, print "Fizz." If it's divisible by 5 with no remainder, print "Buzz." However—and this is the crucial part—if the number is divisible by both 3 and 5 (like 15, 30, or 45), print "FizzBuzz." This seemingly simple problem tests your understanding of conditional logic, modular arithmetic, and control flow—core programming concepts that translate across all languages.

Let's build our solution step by step. First, we'll generate our range of numbers using Python's range() function, which takes start, stop, and step parameters. We'll start at 1, stop at 101 (remember, the stop parameter is exclusive), and step by 1. Initially, let's print each number to verify our range is working correctly.

Now comes the logic that separates junior developers from seasoned programmers. We need to check divisibility using the modulo operator (%). When a number divides evenly with no remainder, the modulo operation returns 0. So our first condition checks: if number % 3 == 0, we print "Fizz" alongside the number for clarity during testing.

Next, we'll add our second condition using an elif statement. When number % 5 == 0, we want to print "Buzz." The choice between if and elif here might seem trivial, but it's actually crucial for proper program flow—something many candidates miss during interviews.

Finally, we'll add an else statement to catch any numbers that don't meet our divisibility criteria, simply printing the number itself. This gives us a complete view of our program's behavior during development.

When we run this code, we'll see "Fizz" for multiples of 3, "Buzz" for multiples of 5, and "FizzBuzz" for numbers like 15, 30, 45, 60, 75, 90—the multiples of both 3 and 5. This pattern demonstrates the mathematical relationship between these numbers and reinforces why the order of our conditional statements matters.

Here's the critical insight that trips up many developers: the order of operations is paramount. The condition checking for numbers divisible by both 3 and 5 must come first in your if-elif chain. If you check for divisibility by 3 first, numbers like 15 will trigger the "Fizz" condition and never reach the "FizzBuzz" check. This logical sequencing is exactly what interviewers are evaluating—your ability to think through edge cases and program flow.

That's FizzBuzz solved—a deceptively simple problem that reveals deep understanding of programming fundamentals. In my next video, I'll tackle another interview favorite: building a multiplication table using the range() function, where we'll explore nested loops and formatted output.