Python Coding challenge - Day 265 | What is the output of the following Python Code?

 

Step-by-Step Explanation

1. Define the List

nums = [1, 2, 3, 4]

A list called nums is defined with the elements [1, 2, 3, 4].

This is the input list we will process using the map() function.

2. Map with lambda to Square Each Element

result = list(map(lambda x: x * x, nums))

What is map()?

map() applies a function to each item in an iterable (in this case, nums) and returns a map object.

Syntax:

map(function, iterable)

function: A function that will be applied to each element.

iterable: A list (or other iterable) whose elements will be processed.

Lambda Function

lambda x: x * x

This is a lambda function, which is a short anonymous function.

It takes a single argument x and returns 

 (the square of x).

Applying map()

map(lambda x: x * x, nums)

map() applies the lambda function lambda x: x * x to each element of the list nums.

Convert the Map Object to a List

list(map(lambda x: x * x, nums))

The map() function returns a map object by default, which is an iterator.

We convert this iterator into a list using list().

After conversion, the result becomes: [1, 4, 9, 16].

So now:

result = [1, 4, 9, 16]

3. Calculate the Sum of the Mapped Results

result = sum(result)

What is sum()?

The built-in sum() function computes the sum of all elements in the given list.

Apply it to the List

We now compute:

sum([1, 4, 9, 16])

result = 30

4. Print the Final Result

print(result)

This will output the computed sum of the squares.

Final Output

The program will print:

30