Python program to remove K length words in String

In this article, we will learn how to remove all words of a specific length (K) from a string using Python. This is useful for text processing tasks where you need to filter words based on their character count.

Problem Statement

Given an input string and a value K, we need to remove all words that have exactly K characters and return the modified string.

Example

inputString = "hello tutorialspoint python codes"
k_length = 5

The output will be ?

Resultant string after removing 5 length words:
tutorialspoint python

In this example, words like hello and codes (both 5 characters long) are removed, leaving tutorialspoint and python.

Using List Comprehension with split() and join()

This approach splits the string into words, filters out K-length words using list comprehension, then joins the remaining words back into a string ?

# Input string and K value
inputString = "hello tutorialspoint python codes"
k_length = 5

print("Input string:", inputString)

# Split string into words and filter out K-length words
words = inputString.split()
filtered_words = [word for word in words if len(word) != k_length]

# Join filtered words back into a string
result = ' '.join(filtered_words)

print("Resultant string after removing", k_length, "length words:")
print(result)

Input string: hello tutorialspoint python codes
Resultant string after removing 5 length words:
tutorialspoint python

Using filter() with Lambda Function

The filter() function with a lambda expression provides a functional programming approach to filter words ?

# Input string and K value
inputString = "hello tutorialspoint python codes"
k_length = 5

print("Input string:", inputString)

# Split and filter using filter() and lambda
words = inputString.split()
filtered_words = list(filter(lambda word: len(word) != k_length, words))

# Join back to string
result = ' '.join(filtered_words)

print("Resultant string after removing", k_length, "length words:")
print(result)

Input string: hello tutorialspoint python codes
Resultant string after removing 5 length words:
tutorialspoint python

Using Loop with remove() Method

This approach iterates through a copy of the word list and removes K-length words using the remove() method ?

# Input string and K value
inputString = "hello tutorialspoint python codes"
k_length = 5

print("Input string:", inputString)

# Split into words
words = inputString.split()

# Iterate through copy and remove K-length words
for word in words.copy():
    if len(word) == k_length:
        words.remove(word)

# Join remaining words
result = ' '.join(words)

print("Resultant string after removing", k_length, "length words:")
print(result)

Input string: hello tutorialspoint python codes
Resultant string after removing 5 length words:
tutorialspoint python

Comparison

Conclusion

List comprehension is the most Pythonic and efficient approach for removing K-length words from a string. Use filter() with lambda for functional programming style, and the loop method when you need to modify the original list in place.