Joining strings characters one after one

Question

How to join two or more strings in python with one character after another?

For example

a = 'hello'
b = 'world'

output = 'hweolellod'

Same goes for three or more strings. using + is not helping.

Answer 1

You could try this:

''.join([x + y for x, y in zip(a, b)])

which gives:

'hweolrllod'

Answer 2

One way is to use str.join with itertools:

from itertools import chain, zip_longest

a = 'hello'
b = 'world'

zipper = zip_longest(a, b, fillvalue='')
res = ''.join(list(chain.from_iterable(zipper)))

print(res)

hweolrllod

Explanation

• zip_longest is used to account for inconsistent length strings.
• zipper here is a lazy iterator which iterates each character of a and b simultaneously by index.
• List creation, while not necessary, is more efficient with str.join.