Python program to convert a list to string

Given a list, write a Python program to convert the given list to string. There are various situations we might encounter when a list is given and we convert it to string. For example, conversion to string from the list of string or the list of integer. 

Example:

Input: ['Geeks', 'for', 'Geeks']
Output: Geeks for Geeks

Input: ['I', 'want', 4, 'apples', 'and', 18, 'bananas']
Output: I want 4 apples and 18 bananas

Let’s see various ways we can convert the list to string. 

Method #1: Iterate through the list and keep adding the element for every index in some empty string. 

Python3

# Python program to convert a list to string

# Function to convert


def listToString(s):

    # initialize an empty string
    str1 = ""

    # traverse in the string
    for ele in s:
        str1 += ele

    # return string
    return str1


# Driver code
s = ['Geeks', 'for', 'Geeks']
print(listToString(s))

Output

GeeksforGeeks

Time Complexity: O(n)
Auxiliary Space: O(n)

Method #2: Using .join() method

Python3

# Python program to convert a list
# to string using join() function

# Function to convert
def listToString(s):

    # initialize an empty string
    str1 = " "

    # return string
    return (str1.join(s))


# Driver code
s = ['Geeks', 'for', 'Geeks']
print(listToString(s))

But what if the list contains both string and integer as its element. In those cases, above code won’t work. We need to convert it to string while adding to string. 

Method #3: Using list comprehension

Python3

# Python program to convert a list
# to string using list comprehension

s = ['I', 'want', 4, 'apples', 'and', 18, 'bananas']

# using list comprehension
listToStr = ' '.join([str(elem) for elem in s])

print(listToStr)

Output

I want 4 apples and 18 bananas

The time complexity of the program is O(n), where n is the length of the list s, because it iterates over each element of the list once.

The auxiliary space complexity of the program is O(n), because it creates a new list of strings using a list comprehension.

Method #4: Using map() Use map() method for mapping str (for converting elements in list to string) with given iterator, the list. 

Python3

# Python program to convert a list
# to string using list comprehension

s = ['I', 'want', 4, 'apples', 'and', 18, 'bananas']

# using list comprehension
listToStr = ' '.join(map(str, s))

print(listToStr)

Output

I want 4 apples and 18 bananas

The time complexity of this code is O(n), where n is the length of the list s. 
The space complexity of this code is O(n), where n is the length of the list s.

Method #5: Using enumerate function

Python3

s = ['I', 'want', 4, 'apples', 'and', 18, 'bananas']

listToStr = ' '.join([str(elem) for i,elem in enumerate(s)])

print(listToStr)

Output

I want 4 apples and 18 bananas

Method #6: Using in operator

Python3

s = ['Geeks', 'for', 'Geeks']
for i in s:
  print(i,end=" ")

Output

Geeks for Geeks 

Method #7: Using functools.reduce method

Python

from functools import reduce
s = ['I', 'want', 4, 'apples', 'and', 18, 'bananas']

listToStr = reduce(lambda a, b : a+ " " +str(b), s)

print(listToStr)

Output

I want 4 apples and 18 bananas

Using str.format method:

One additional approach to convert a list to a string in Python is to use the str.format method. This method allows you to specify a string template, and then fill in the placeholder values with the elements in the list.

For example:

Python3

lst = ['Geeks', 'for', 'Geeks']

# Convert the list to a string using str.format
result = "{} {} {}".format(*lst)

print(result)  # Output: Geeks for Geeks
#This code is contributed by Edula Vinay Kumar Reddy

Output

Geeks for Geeks

This approach has the advantage of being able to specify exactly how the elements in the list should be formatted, by using the formatting placeholders in the string template. For example, you can specify the number of decimal places for floating point numbers, or the width and alignment of the output string.

Python3

lst = [1.2345, 'good' , 3.4567]

# Convert the list to a string using str.format
result = "{:.2f} {} {:.2f}".format(*lst)

print(result)  # Output: 1.23 2.35 3.46
#This code is contributed by Edula Vinay Kumar Reddy

Output

1.23 good 3.46

The time complexity of the above approaches will depend on the length of the list. For example, in method 1, we are iterating through the list and adding each element to a string, so the time complexity will be O(n), where n is the length of the list.

Similarly, the time complexity of other methods will also be O(n).

The space complexity of all the above methods will also be O(n) as we are creating a new string of size n to store the elements of the list.

Method #8: Using Recursion 

Python3

def list_string(start,l,word):
  if start==len(l):return word #base condition to return string
  word+=str(l[start])+' ' #concatenating element in list to word variable
  return list_string(start+1,l,word)  #calling recursive function

#Driver code
l=['Geeks','for','Geeks']  #defining list
print(list_string(0,l,''))

Output

Geeks for Geeks