Concatenate elements from two lists into a third one in python

Question

a = ['1', '2', '3']
b = ['a', 'b', 'c']
c = []

What can I do to get the third list to be the concatenation of the corresponding elements from lists a and b, as in:

c = ['1a', '2b', '3c']

Or using string formatting f'{x}{y}' in place of x + y in the above. — alani
– alani, Commented Aug 11, 2020 at 3:08

Gavin Wong · Accepted Answer · 2020-08-11 03:14:21Z

1

Here is a simple while loop to do the trick:

a = ['1', '2', '3']
b = ['a', 'b', 'c']
c = []

counter = 0
while counter < len(a):
    c.append(a[counter] + b[counter])
    counter += 1

print(c)

Obviously, there are more elegant methods to do this, such as using the zip method:

a = ['1', '2', '3']
b = ['a', 'b', 'c']
c = [x + y for x,y in zip(a, b)]

print(c)

Both methods have the same output:

['1a', '2b', '3c']

answered Aug 11, 2020 at 3:14

Gavin Wong

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Comments

Kevin Yu · Accepted Answer · 2020-08-11 05:31:54Z

1

You can use a enumerate function to elegantly solve your problem.

a = ['1', '2', '3']
b = ['a', 'b', 'c']
c = []
for idx, elem in enumerate(a):
  c.append(a[idx] + b[idx])
print(c)

answered Aug 11, 2020 at 5:31

Kevin Yu

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