When working with strings in Python, it is often necessary to manipulate and rearrange the words within a sentence. One common task is to arrange a list of words based on their order of appearance in the original sentence. In this article, we will explore three different approaches to solve this problem.

Approach 1: Using the sorted() function

The sorted() function in Python can be used to sort any iterable, including lists. To solve the given problem, we can split the sentence into a list of words using the split() method, and then sort the list based on the index of each word in the original sentence.

sentence = "Arrange list by which word comes first in given sentence string in python"
words = sentence.split()
sorted_words = sorted(words, key=lambda x: sentence.index(x))
print(sorted_words)

This approach works by using a lambda function as the key parameter in the sorted() function. The lambda function takes each word in the list and returns its index in the original sentence. This ensures that the words are sorted based on their order of appearance in the sentence.

Approach 2: Using a custom sorting function

Another way to solve this problem is by creating a custom sorting function. This function will compare two words based on their indices in the original sentence and return the appropriate sorting order.

sentence = "Arrange list by which word comes first in given sentence string in python"
words = sentence.split()

def custom_sort(word):
    return sentence.index(word)

sorted_words = sorted(words, key=custom_sort)
print(sorted_words)

In this approach, we define a custom_sort() function that takes a word as input and returns its index in the original sentence. We then pass this function as the key parameter to the sorted() function, which sorts the words based on the custom sorting order.

Approach 3: Using a dictionary

A third approach to solve this problem is by using a dictionary to store the indices of each word in the original sentence. We can then sort the words based on their corresponding indices in the dictionary.

sentence = "Arrange list by which word comes first in given sentence string in python"
words = sentence.split()
word_indices = {word: sentence.index(word) for word in words}
sorted_words = sorted(words, key=lambda x: word_indices[x])
print(sorted_words)

In this approach, we create a dictionary called word_indices, where the keys are the words in the sentence and the values are their corresponding indices. We then use a lambda function as the key parameter in the sorted() function to sort the words based on their indices in the dictionary.

After exploring these three approaches, it is clear that the first approach using the sorted() function is the most concise and efficient solution. It requires only a single line of code and does not involve creating any additional functions or dictionaries. Therefore, the first approach is the recommended solution for arranging a list of words based on their order of appearance in a given sentence string in Python.