412. Fizz Buzz

Problem¶

Return a list of strings for numbers 1..n:

• "FizzBuzz" if the number is divisible by 15
• "Fizz" if divisible by 3
• "Buzz" if divisible by 5
• otherwise the number itself as a string

Example:

• n = 6 -> ["1", "2", "Fizz", "4", "Buzz", "Fizz"]

Key trick¶

Check the combined case first:

• divisibility by 15
• then 3
• then 5

This avoids incorrectly returning "Fizz" or "Buzz" for multiples of both.

Trap¶

Common mistakes:

• checking 3 and 5 before 15
• using 0..n-1 instead of 1..n
• returning integers instead of strings

Why is it interesting?¶

It is simple but tests:

• careful condition ordering
• off-by-one handling
• clean loop and string construction

Python solution¶

class Solution:
    def fizzBuzz(self, n: int) -> list[str]:
        res = []

        # Build the result from 1 to n inclusive.
        for i in range(1, n + 1):
            if i % 15 == 0:
                res.append("FizzBuzz")
            elif i % 3 == 0:
                res.append("Fizz")
            elif i % 5 == 0:
                res.append("Buzz")
            else:
                res.append(str(i))

        return res

Comment on my solution¶

Not provided.