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While Loops in Python

 

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While Loops in Python

The while loop in Python is used to repeatedly execute a block of code as long as a condition is true. The loop will continue to run as long as the condition remains true.

Basic While Loop

The basic syntax of a while loop in Python is:


# Basic while loop example
while condition:
    # Code to execute

For example, a loop that prints numbers from 1 to 5:


# Printing numbers from 1 to 5
count = 1

while count <= 5:
    print(count)
    count += 1

Using Break in While Loops

The break statement can be used to exit the loop prematurely when a certain condition is met.


# Using break in a while loop
count = 1

while count <= 5:
    if count == 3:
        break
    print(count)
    count += 1

Using Continue in While Loops

The continue statement can be used to skip the current iteration and proceed to the next iteration of the loop.


# Using continue in a while loop
count = 0

while count < 5:
    count += 1
    if count == 3:
        continue
    print(count)

Infinite Loops

If the condition in a while loop never becomes false, the loop will continue to execute indefinitely. Be careful to avoid infinite loops, as they can cause your program to hang.


# Infinite loop example

while True:
    print("This will run forever...")

Using Else with While Loops

An optional else block can be used with a while loop. The else block is executed when the loop condition becomes false.


# Using else with while loops
count = 1

while count <= 5:
    print(count)
    count += 1
else:
    print("Loop completed.")
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