Python Coding challenge - Day 666| What is the output of the following Python Code?

 

Code Explanation:

Import NumPy

import numpy as np

Loads the NumPy library into your program.

The alias np is just a short name for convenience.

NumPy is great for working with arrays and doing fast numerical operations.

Create an array with multiplication

arr = np.arange(1, 6) * 4

np.arange(1, 6) creates a NumPy array:

[1, 2, 3, 4, 5]

(starts at 1, ends before 6).

* 4 multiplies each element by 4:

[4, 8, 12, 16, 20]

Now arr is:

array([ 4,  8, 12, 16, 20])

Apply a condition and update elements

arr[arr % 3 == 1] += 5

arr % 3 gives the remainder when each element is divided by 3:

[1, 2, 0, 1, 2]

arr % 3 == 1 creates a boolean mask:

[ True, False, False, True, False ]

(True where the remainder is 1).

arr[arr % 3 == 1] selects only the elements that match the condition:

From [4, 8, 12, 16, 20] → [4, 16]

+= 5 adds 5 to each of those elements:

4 becomes 9

16 becomes 21

Now arr is:

array([ 9,  8, 12, 21, 20])

Calculate the sum

print(arr.sum())

arr.sum() adds all elements together:

9 + 8 + 12 + 21 + 20 = 70

Output:

70

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