FizzBuzz: Multi-Threaded Concurrent FizzBuzz in Java (CTCI 15.7)

TL;DR

• The Problem: CTCI problem 15.7 technical mechanics.
• The Approach: CTCI problem 15.7: multi-threaded FizzBuzz using 4 concurrent threads for numbers divisible by 3, 5, 15, and others.
• Complexity: Optimal Time and Memory bounds.

This article provides a clear breakdown of CTCI problem 15.7.

1. Context and Problem Statement

CTCI problem 15.7: multi-threaded FizzBuzz using 4 concurrent threads for numbers divisible by 3, 5, 15, and others.

2. Technical Code & Mechanics

public class MultithreadedFizzBuzz {
    private int n;
    private int current = 1;
    public synchronized void fizz() throws InterruptedException {
        while (current <= n) {
            if (current % 3 == 0 && current % 5 != 0) {
                System.out.println("Fizz");
                current++;
                notifyAll();
            } else wait();
        }
    }
}

3. Key Takeaways and Edge Cases

Always test boundary conditions and invalid input states.