Python | Check for Whitespace in List

Sometimes, we might have a problem in which we need to check if the List of strings has any of blank spaces. This kind of problem can be in Machine Learning domain to get specific type of data set. Let’s discuss certain ways in which this kind of problem can be solved. 

Method #1: Using regex + any() This kind of problem can be solved using the regex utility offered by python. By feeding the appropriate regex string in search(), we can check presence of space in a string and iterate through entire list using any(). 

Python3

# Python3 code to demonstrate working of
# Check for Whitespace in List
# Using regex and any()
import re

# initializing list
test_list = ["Geeks forGeeks", "is", "best"]

# printing original list
print("The original list is : " + str(test_list))

# Check for Whitespace in List
# Using regex and any()
res = any(bool(re.search(r"\s", ele)) for ele in test_list)

# printing result
print("Does any string contain spaces ? " + str(res))

Output

The original list is : ['Geeks forGeeks', 'is', 'best']
Does any string contain spaces ? True

Time Complexity: O(n) where n is the number of elements in the string list. The regex + any() is used to perform the task and it takes O(n) time.
Auxiliary Space: O(1) constant additional space is required

Method #2: Using in operator + any() This task can also be performed using in operator. Just required to check for a space in the string. The verdict returned is true even if a single space is found in any of string of list and false otherwise. 

Python3

# Python3 code to demonstrate working of
# Check for Whitespace in List
# Using in operator + any()
import re

# initializing list
test_list = ["Geeks forGeeks", "is", "best"]

# printing original list
print("The original list is : " + str(test_list))

# Check for Whitespace in List
# Using in operator + any()
res = any('' in ele for ele in test_list)

# printing result
print("Does any string contain spaces ? " + str(res))

Output

The original list is : ['Geeks forGeeks', 'is', 'best']
Does any string contain spaces ? True

Time Complexity: O(n), where n is the number of elements in the list “test_list”.
Auxiliary Space: O(1), constant additional space required

Method #3 : Using count() method

Python3

# Python3 code to demonstrate working of
# Check for Whitespace in List

# initializing list
test_list = ["Geeks forGeeks", "is", "best"]

# printing original list
print("The original list is : " + str(test_list))

# Check for Whitespace in List
res=False
for i in test_list:
    if(i.count(" ")>=1):
        res=True
        break
# printing result
print("Does any string contain spaces ? " + str(res))

Output

The original list is : ['Geeks forGeeks', 'is', 'best']
Does any string contain spaces ? True

Method #4: Using list comprehension and join()

Python3

# Python3 code to demonstrate working of
# Check for Whitespace in List
# Using list comprehension and join()

# initializing list
test_list = ["Geeks forGeeks", "is", "best"]

# printing original list
print("The original list is : " + str(test_list))

# Check for Whitespace in List
# Using list comprehension and join()
res = " " in "".join(test_list)

# printing result
print("Does any string contain spaces ? " + str(res))
#This code is contributed by Edula Vinay Kumar Reddy

Output

The original list is : ['Geeks forGeeks', 'is', 'best']
Does any string contain spaces ? True

Time complexity: O(n)
Auxiliary space: O(1)

Method #5: Using loop and if condition:

Python3

# Initializing the list of strings
test_list = ["Geeks forGeeks", "is", "best"]

# Printing the original list
print("The original list is : " + str(test_list))

# Using a for loop to check if any string contains a space character
flag = False # flag to keep track of whether any string contains a space character
for i in test_list:
  if " " in i: # checking if current string has a space character
    print("Does any string contain spaces ? ",True)
    flag = True
    break # breaking the loop if a space character is found

# printing the final result if the loop completes without finding a space character
if not flag:
  print("Does any string contain spaces ? ",False)
#this code is contributed by Shaik_Asif

Output

The original list is : ['Geeks forGeeks', 'is', 'best']
Does any string contain spaces ?  True

 Time complexity: O(n)
Auxiliary space: O(1)

Method #5: Using isspace():

Python3

test_list = ["Geeks forGeeks", "is", "best"]
print("The original list is : " + str(test_list))
res = False
for ele in test_list:
    if any(c.isspace() for c in ele):
        res = True
        break
print("Does any string contain spaces ? " + str(res))
#This code is contributed by Jyothi pinjala.

Output

The original list is : ['Geeks forGeeks', 'is', 'best']
Does any string contain spaces ? True

Time complexity: O(n*m)
Auxiliary space: O(1)