Concatenating Strings: "Multiplication" of two list of strings

Question

For list of strings, define the multiplication operation in as concatenating here:

l1 = ['aa', 'bb', 'cc']
l2 = ['11', '22']
l3 = l1 op l2

Expected output:

l3 = ['aa11', 'aa22', 'bb11', 'bb22', 'cc11', 'cc22']

Simply we can use

for l in l1:
    for ll in l2:
        l3.append(l+ll)

But I'd be grateful to hear a pythonic solution.

What is "not pythonic" here? Do you mean "code that is hardly to understand = pythonic"? Think of developers who will support your code. They will be glad to have this logic exactly in such form (nested loops) as your have done. The solution of @jedwards is also good from the point of view of maintainability and understanding. — mentallurg, Jun 04 '18 at 22:42
@OlivierMelançon Correct. It should be phrased as multilication. — CH_skar, Jun 05 '18 at 02:07
Does this answer your question? [concatenate strings in 2 different lists in python](https://stackoverflow.com/questions/36885876/concatenate-strings-in-2-different-lists-in-python) — Georgy, May 09 '20 at 14:47

score 4 · Accepted Answer · answered Jun 04 '18 at 22:37

4

from itertools import product

l1 = ['aa', 'bb', 'cc']
l2 = ['11', '22']

l3 = [x+y for (x,y) in product(l1,l2)]

print(l3)

But it's effectively the same thing as what you're doing (provided you fix the typo :P)

answered Jun 04 '18 at 22:37

jedwards

score 2 · Answer 2 · answered Jun 04 '18 at 22:37

2

l3 = [a+b for a in l1 for b in l2]

answered Jun 04 '18 at 22:37

iacob

2 Answers2