Python Coding challenge - Day 681| What is the output of the following Python Code?

 

Code Explanation:

1) Imports

import itertools

import operator

itertools → provides fast iterator building blocks.

operator → exposes function versions of Python’s operators (like +, *, etc.). We’ll use operator.mul for multiplication.

2) Input sequence

nums = [1,2,3,4]

A simple list of integers we’ll “accumulate” over.

3) Cumulative operation

res = list(itertools.accumulate(nums, operator.mul))

itertools.accumulate(iterable, func) returns an iterator of running results.

Here, func is operator.mul (i.e., multiply).

So it computes a running product:

Start with first element → 1

Step 2: previous 1 × next 2 → 2

Step 3: previous 2 × next 3 → 6

Step 4: previous 6 × next 4 → 24

Converting the iterator to a list gives: [1, 2, 6, 24].

Note: If you omit operator.mul, accumulate defaults to addition, so accumulate([1,2,3,4]) would yield [1, 3, 6, 10].

4) Output

print(res)

Prints the cumulative products:

[1, 2, 6, 24]

Download Book - 500 Days Python Coding Challenges with Explanation