Looping concepts in Python

Friendly Python

In Python, looping concepts are essential for executing a set of instructions repeatedly. Whether we want to iterate over a sequence of elements or repeat a block of code based on a specific condition we need the loops in these case.

Python provides two main looping concepts:

'for' loop
'while' loop

The for and while loops provide powerful looping constructs that allow us to automate repetitive tasks and iterate over sequences or based on specific conditions. The for loop is suitable for iterating over sequences like lists, strings, or other iterable objects, while the while loop is ideal when we need to repeat a block of code until a condition becomes false.

In this article, we will look into these looping concepts, understand their syntax, and explore their applications in different scenarios.

'for ' Loop :

The 'for' loop is widely used in Python for iterating over a sequence of elements. It allows us to execute a block of code for each element in the sequence.

The basic syntax of a for loop is as follows:

                
                  
                    for element in sequence:
                        # code block to execute

The loop iterates over the elements in the sequence, assigning each element to the variable element in each iteration. The code block inside the loop is then executed.

Here's an example:

                
                  
                    fruits = ['apple', 'banana', 'orange']

                    for fruit in fruits:
                        print(fruit)

In this example, the for loop iterates over the elements in the list of fruits, and the variable fruit takes the value of each element in each iteration. The code block inside the loop (print(fruit)) is executed for each element, resulting in the printing of each fruit.

The range() function is commonly used with 'for' loops to generate a sequence of numbers.
For example:

                
                  
                    for i in range(1, 6):
                        print(i)

'while ' Loop :

The while loop is used when we want to repeat a block of code as long as a certain condition is true. It repeatedly executes the code block until the condition becomes false.

The basic syntax of a while loop is as follows:

                
                  
                    while condition:
                      # code block to execute

The loop continues as long as the condition remains true. It is crucial to ensure that the condition eventually becomes false to avoid an infinite loop.
Here's an example:

                
                  
                    count = 1

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

In this example, the while loop executes the code block as long as the condition count ' <= 5 ' is true. The variable count starts with a value of 1, and in each iteration, it is incremented by 1. The loop prints the value of count and continues until it reaches a value greater than 5.

The while loop is often used when the number of iterations is uncertain or based on dynamic conditions.