Python Multi-threading and Concurrency: Concurrent even and odd number printing

Last update on April 24 2025 12:40:57 (UTC/GMT +8 hours)

3. Even and Odd Printer Threads

Write a Python program that creates two threads to find and print even and odd numbers from 30 to 50.

Sample Solution:

Python Code:

import threading
def print_even_numbers():
    print("List of even numbers:")
    for i in range(30, 51, 2):
        print(i, end = " ")

def print_odd_numbers():
    print("\nList of odd numbers:")
    for i in range(31, 51, 2):
        print(i, end = " ")
# Create threads for printing even and odd numbers
even_thread = threading.Thread(target=print_even_numbers)
odd_thread = threading.Thread(target=print_odd_numbers)
# Start the threads
even_thread.start()
odd_thread.start()
# Wait for the threads to complete
even_thread.join()
odd_thread.join()

Sample Output:

List of even numbers:
30 32 34 36 38 40 42 44 46 48 50 
List of odd numbers:
31 33 35 37 39 41 43 45 47 49

Explanation:

In the above exercise,

We define two functions: "print_even_numbers()" and "print_odd_numbers()".
The "print_even_numbers()" function uses a loop to print even numbers from 30 to 50, incrementing by 2.
The "print_odd_numbers()" function does the same for odd numbers, starting at 31 and incrementing by 2.
Create two threads, "even_thread" and "odd_thread", targeting their respective functions.
Start the threads using the start() method, which initiates their parallel execution.
Finally, we use the join() method to wait for threads to complete.

Flowchart:

For more Practice: Solve these Related Problems:

Write a Python program that creates two threads: one to print even numbers and another to print odd numbers from 30 to 50 concurrently.
Write a Python script that uses two threads to separate and print even and odd numbers from a given range, then synchronizes the output in ascending order.
Write a Python function that starts one thread to print even numbers and another to print odd numbers, and then merges the outputs into a single sorted list.
Write a Python program to alternate between two threads—one printing even and one printing odd numbers from 30 to 50—ensuring no interleaving errors occur.

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