What are the main challenges that can arise when using multithreaded programming?

The main challenges of multithreaded programming are related to parallel code execution and access to shared resources:

• Race conditions: when multiple threads modify the same data simultaneously without synchronization, leading to unpredictable results.

• Deadlocks: situations where two or more threads wait for each other, causing the program to halt.

• Starvation: when one thread constantly gains access to a resource while others do not.

• Debugging complexity: errors in multithreaded code are often difficult to reproduce and fix.

• State management: the need to properly synchronize access to shared data using mechanisms such as synchronized, locks, volatile, etc.

An example in Java — using synchronized to protect a critical section:

public class Counter {
    private int count = 0;

    public synchronized void increment() {
        count++;
    }

    public synchronized int getCount() {
        return count;
    }
}

Without synchronization, errors may occur when calling increment concurrently from different threads.