Python basic for loop clarification

Question

I have 3 years of PHP experience and currently trying to catch up with Python on sololearn. The first question in Intermediate Python that checks my Python knowledge goes like this:

n = [2, 4, 6, 8]
res = 1
for x in n[1:3]:
  res *= x

I am confused why the result is 24, my logic is that n[1:3] means n[1] * n[2] * n[3] so 4 * 6 * 8.

I searched on google about for loops in Python but i only find stuff about the range() function, couldn't find an explanation for the : operator

Hint: `print([2, 4, 6, 8][1:3])`. Your loop iterates over the list returned from that — OneCricketeer, Jun 02 '22 at 19:51
`range` and slicing work the same way: the upper bound is *exclusive*. `list(range(1, 3)) == [1,2,3][1:3] == [1,2]`. — chepner, Jun 02 '22 at 19:54

score 1 · Answer 1 · answered Jun 02 '22 at 19:53

1

It does n[1] * n[2] = 4 *6 = 24. Read more about list slicing: https://railsware.com/blog/python-for-machine-learning-indexing-and-slicing-for-lists-tuples-strings-and-other-sequential-types/

answered Jun 02 '22 at 19:53

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Python basic for loop clarification

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