A while loop in Python is a control flow structure that allows you to repeatedly execute a block of code as long as a certain condition remains true. The loop will continue to run until the condition evaluates to False. It is useful when you want to create a loop that continues until a specific condition is met, and the number of iterations is not known in advance.
Here is the basic syntax of a while loop in Python:
while condition:
# Code to be executed as long as the condition is True
- `condition`: This is an expression that determines whether the loop should continue running or not. It must be a Boolean expression, meaning it should evaluate to either `True` or `False`.
Here's an example to illustrate how a while loop works:
# Initialize a variable
count = 1
# Define the while loop with a condition
while count <= 5:
# This block of code will execute as long as count is less than or equal to 5
print("Count is:", count)
count += 1 # Increment the count by 1 in each iteration
# The loop exits when the condition count <= 5 becomes False
print("Loop finished!")
In this example, the while loop runs as long as the `count` variable is less than or equal to 5. Inside the loop, it prints the current value of `count` and then increments it by 1 in each iteration. When `count` becomes 6, the condition becomes False, and the loop terminates.
The output of this code will be:
Count is: 1 Count is: 2 Count is: 3 Count is: 4 Count is: 5 Loop finished!
It's important to be careful when using while loops to ensure that the loop will eventually exit. If the condition never becomes False, you will create an infinite loop, which can crash your program or computer. Therefore, make sure to include logic in your loop to ensure it terminates when necessary.
