While Loops

‍Loops are used to iterate through the same block of code multiple times. A for loop will keep executing the same block of code until it has iterated through the entire iterable (list, dictionary or tuple).

while loops are different than for loops. A while loop will keep running a block of code repeatedly until a specified condition becomes False. The skeleton for a while loop is as follows:

while (condition):
	//execute code

In this article, you're going to learn how to use while loops to repeatedly execute a block of code based on a condition.

‍While loops in action

You will start by defining a while loop that keeps printing a random number while the random number remains less than 30

random_number = 25

while random_number < 30:
	print(random_number)

>>20

>>20

>>20

>>.......

The code runs forever! Stop the code's execution from the Runtime menu.

The code runs forever because the while loop is configured to keep running while random_number is less than 30. The condition random_number < 30 will always be True since random_number will always be equal to 25.

This can be fixed by incrementing random_number by 1 in each iteration.

while random_number < 30:
  random_number += 1
  print(random_number)

>>26

>>27

>>28

>>29

>>30

In each iteration, random_number is incremented by 1 until it reaches 30. random_number eventually becomes large enough to render the condition False, breaking the while loop.‍

‍That wraps it up for while loops. They are as simple as they seem!

In summary, a while loop will repeatedly execute a block of code until its condition stops being met. Try playing around with the condition and see what type of results you get!