Python – Horizontal Concatenation of Multiline Strings

Given pair of strings, which is multiline, perform concatenation horizontally.

Examples:

Input : 
test_str1 = ”’ 
geeks for 
geeks”’, 
test_str2 = ”’ 
is 
best”’ 
Output : 
geeks foris 
geeksbest 
Explanation : 1st line joined with 1st line of 2nd string, “geeks for” -> “is”.

Input : 
test_str1 = ”’ 
geeks for ”’ 
test_str2 = ”’ 
geeks ”’ 
Output : 
geeks for geeks 
Explanation : 1st line joined with 1st line of 2nd string, “geeks for ” -> “geeks”. 

Method #1 : Using zip() + split() + join() + list comprehension

In this, we perform the task of splitting by “\n” using split(), and they are paired together using zip(). The next step is joining both the zipped strings for horizontal orientation using “\n” and join().

Python3

# Python3 code to demonstrate working of
# Horizontal Concatenation of Multiline Strings
# Using zip() + split() + join() + list comprehension

# initializing strings
test_str1 = '''
geeks 4
geeks'''

test_str2 = '''
is
best'''

# printing original strings
print("The original string 1 is : " + str(test_str1))
print("The original string 2 is : " + str(test_str2))

# split lines
splt_lines = zip(test_str1.split('\n'), test_str2.split('\n'))

# horizontal join
res = '\n'.join([x + y for x, y in splt_lines])

# printing result
print("After String Horizontal Concatenation : " + str(res))

Output

The original string 1 is : 
geeks 4
geeks
The original string 2 is : 
is
best
After String Horizontal Concatenation : 
geeks 4is
geeksbest

Time Complexity: O(n)

Auxiliary Space: O(n)

Method #2 : Using map() + operator.add + join()

In this, we use map() to with help of add() to perform concatenation, split() is used to perform initial split by “\n”.

Python3

# Python3 code to demonstrate working of
# Horizontal Concatenation of Multiline Strings
# Using map() + operator.add + join()
from operator import add

# initializing strings
test_str1 = '''
geeks 4
geeks'''
test_str2 = '''
is
best'''

# printing original strings
print("The original string 1 is : " + str(test_str1))
print("The original string 2 is : " + str(test_str2))

# using add to concat, map() to concat each lines zipped
res = '\n'.join(map(add, test_str1.split('\n'), test_str2.split('\n')))

# printing result
print("After String Horizontal Concatenation : " + str(res))

Output

The original string 1 is : 
geeks 4
geeks
The original string 2 is : 
is
best
After String Horizontal Concatenation : 
geeks 4is
geeksbest

Time Complexity: O(n) -> ( join function)

Auxiliary Space: O(n)