Python Loops

Loops are used in programming to repeat a specific block of code until a certain condition is met. Python has two types of loops: for loop and while loop.

Syntax

For loop

for variable in sequence:
    # code block to be executed

While loop

while condition:
    # code block to be executed

Example

For loop

fruits = ["apple", "banana", "cherry"]
for fruit in fruits:
    print(fruit)

While loop

i = 1
while i < 6:
    print(i)
    i += 1

Output

For loop

apple
banana
cherry

While loop

1
2
3
4
5

Explanation

• A for loop is used to iterate over a sequence (list, tuple, dictionary, set, or string).
• A while loop is used to repeat a block of code as long as a certain condition is true.
• In a for loop, a temporary variable is created to hold the current element of the sequence during each iteration.
• In a while loop, the condition is checked before each iteration.

Use

• Loops are used to iterate over a sequence and perform some operation on each element of the sequence.
• Loops can also be used to repeat a block of code until a certain condition is met, such as validating user input.

Important Points

• Be careful to avoid infinite loops when using while loops. Make sure that the condition will eventually become false.
• Use range() function to generate numbers for iterations.

Summary

Loops are an essential part of programming. They allow you to repeat a block of code until a certain condition is met. Python has two types of loops: for loop and while loop. Use for loop to iterate over a sequence and while loop to repeat a block of code as long as a certain condition is true.