Python Coding challenge - Day 729| What is the output of the following Python Code?

 Code Explanation

1. Importing reduce from functools

from functools import reduce

reduce is a higher-order function in Python.

It repeatedly applies a function to the elements of an iterable, reducing it to a single value.

Syntax:

reduce(function, iterable, initializer(optional))

2. Creating a List

nums = [1, 2, 3, 4]

nums is a list of integers.

Contents: [1, 2, 3, 4].

3. Using reduce with multiplication

res = reduce(lambda x, y: x * y, nums, 2)

The lambda function takes two numbers and multiplies them (x * y).

Initial value is 2 (because of the third argument).

 Step-by-step:

Start with 2.

Multiply with first element: 2 * 1 = 2.

Multiply with second element: 2 * 2 = 4.

Multiply with third element: 4 * 3 = 12.

Multiply with fourth element: 12 * 4 = 48.

Final result: 48.

4. Printing the Result

print(res)

Output:

48

5. Appending a New Element

nums.append(5)

Now nums = [1, 2, 3, 4, 5].

6. Using reduce with addition

res2 = reduce(lambda x, y: x + y, nums)

Here, lambda adds two numbers (x + y).

No initializer is given, so the first element 1 is taken as the starting value.

Step-by-step:

Start with 1.

Add second element: 1 + 2 = 3.

Add third element: 3 + 3 = 6.

Add fourth element: 6 + 4 = 10.

Add fifth element: 10 + 5 = 15.

Final result: 15.

7. Printing the Final Result

print(res2)

Output:

15

Final Output

48

15

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