Question

How to merge two lists alternatively in Python

Answer 1

def MergeAlternatively(lst1, lst2):
    return [sub[element] for element in range(len(lst2))
                      for sub in [lst1, lst2]]

lst1 = [1, 2, 3, 4, 5]
lst2 = ['a', 'b', 'c', 'd', 'e']

lst = MergeAlternatively(lst1, lst2)

print(lst)




'''
run:

[1, 'a', 2, 'b', 3, 'c', 4, 'd', 5, 'e']

'''

 

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Answer 2

def MergeAlternatively(lst1, lst2):
    return [element for pair in zip(lst1, lst2 + [0])
                                 for element in pair]

lst1 = [1, 2, 3, 4, 5]
lst2 = ['a', 'b', 'c', 'd', 'e']

lst = MergeAlternatively(lst1, lst2)

print(lst)




'''
run:

[1, 'a', 2, 'b', 3, 'c', 4, 'd', 5, 'e']

'''

 

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Answer 3

from functools import reduce
import operator

def MergeAlternatively(lst1, lst2):
    return reduce(operator.add, zip(lst1, lst2))

lst1 = [1, 2, 3, 4, 5]
lst2 = ['a', 'b', 'c', 'd', 'e']

lst = MergeAlternatively(lst1, lst2)

print(lst)




'''
run:

[1, 'a', 2, 'b', 3, 'c', 4, 'd', 5, 'e']

'''

 

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Answer 4

import numpy as np

def MergeAlternatively(lst1, lst2):
    return np.array([[i, j] for i, j in zip(lst1, lst2)]).ravel()

lst1 = [1, 2, 3, 4, 5]
lst2 = ['a', 'b', 'c', 'd', 'e']

lst = MergeAlternatively(lst1, lst2)

print(lst)




'''
run:

[1, 'a', 2, 'b', 3, 'c', 4, 'd', 5, 'e']

'''

 

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