To create a while loop in Python:
while condition is true:
perform an action
4 Examples of While Loop in Python
Example 1: Create a Countdown
To start, create a countdown, where:
- The countdown will start at 10
- The value of the countdown will decrease by intervals of 1
- The countdown will stop at 4
Based on the above rules, the condition for the countdown is therefore:
countdown > 3
And so long as this condition is true, the countdown will decrease by intervals of 1.
Here is the full Python code to perform the while loop for our example:
countdown = 10
while countdown > 3:
print("CountDown =", countdown)
countdown = countdown - 1
Once you run the code, you’ll get the following countdown:
CountDown = 10
CountDown = 9
CountDown = 8
CountDown = 7
CountDown = 6
CountDown = 5
CountDown = 4
Example 2: Use a Break
Sometimes you may want to use a ‘break‘ statement to end the loop when a specific condition is met.
You can then achieve the same outcome, as in example 1, by including a break statement as follows:
countdown = 10
while countdown > 0:
print("CountDown =", countdown)
countdown = countdown - 1
if countdown == 3:
break
And when you run the code, you’ll indeed get the same results as in the first example:
CountDown = 10
CountDown = 9
CountDown = 8
CountDown = 7
CountDown = 6
CountDown = 5
CountDown = 4
Example 3: Counting Up
You just saw how to count down, but what if you want to count up?
In this example, you’ll start counting from 1, and then stop at 9 (each time increasing the value of the count by 1).
Here, the condition is:
10 > increment > 0
Putting everything together:
increment = 1
while 10 > increment > 0:
print("Increment =", increment)
increment = increment + 1
And the results:
Increment = 1
Increment = 2
Increment = 3
Increment = 4
Increment = 5
Increment = 6
Increment = 7
Increment = 8
Increment = 9
Example 4: Counting Up with a Break
Now use a ‘break‘ statement to get the same results as in example 3:
increment = 1
while increment > 0:
print("Increment =", increment)
increment = increment + 1
if increment == 10:
break
Run the code and you’ll indeed get the same results as in the third example:
Increment = 1
Increment = 2
Increment = 3
Increment = 4
Increment = 5
Increment = 6
Increment = 7
Increment = 8
Increment = 9
Thanks so much, this really help.
Thanks!