Python: Split a string of words separated by commas and spaces into 2 lists: words and separators

Last update on May 28 2022 13:41:24 (UTC/GMT +8 hours)

Python Programming Puzzles: Exercise-8 with Solution

Write a Python program to split a string of words separated by commas and spaces into two lists, words and separators.

Input:  
W3resource Python, Exercises.
Output:
[['W3resource', 'Python', 'Exercises.'], [' ', ', ']]

Input: 
The dance, held in the school gym, ended at midnight.
Output:

[['The', 'dance', 'held', 'in', 'the', 'school', 'gym', 'ended', 'at', 'midnight.'], [' ', ', ', ' ', ' ', ' ', ' ', ', ', ' ', ' ']]

Input:  
The colors in my studyroom are blue, green, and yellow.
Output:
[['The', 'colors', 'in', 'my', 'studyroom', 'are', 'blue', 'green', 'and', 'yellow.'], [' ', ' ', ' ', ' ', ' ', ' ', ', ', ', ', ' ']]

Pictorial Presentation:

Python: Split a string of words separated by commas and spaces into 2 lists: words and separators.

Sample Solution:

Python Code:

#License: https://bit.ly/3oLErEI

def test(string):
    import re
    merged = re.split(r"([ ,]+)", string)
    return [merged[::2], merged[1::2]]
s = "W3resource Python, Exercises."
print("Original string:",s)
print("Split the said string into 2 lists: words and separators:")
print(test(s))
s = "The dance, held in the school gym, ended at midnight."
print("\nOriginal string:",s)
print("Split the said string into 2 lists: words and separators:")
print(test(s))
s = "The colors in my studyroom are blue, green, and yellow."
print("\nOriginal string:",s)
print("Split the said string into 2 lists: words and separators:")
print(test(s))

Sample Output:

Original string: W3resource Python, Exercises.
Split the said string into 2 lists: words and separators:
[['W3resource', 'Python', 'Exercises.'], [' ', ', ']]

Original string: The dance, held in the school gym, ended at midnight.
Split the said string into 2 lists: words and separators:
[['The', 'dance', 'held', 'in', 'the', 'school', 'gym', 'ended', 'at', 'midnight.'], [' ', ', ', ' ', ' ', ' ', ' ', ', ', ' ', ' ']]

Original string: The colors in my studyroom are blue, green, and yellow.
Split the said string into 2 lists: words and separators:
[['The', 'colors', 'in', 'my', 'studyroom', 'are', 'blue', 'green', 'and', 'yellow.'], [' ', ' ', ' ', ' ', ' ', ' ', ', ', ', ', ' ']]

Flowchart:

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Next: List integers containing exactly three distinct values, such that no integer repeats twice consecutively.

Python: Tips of the Day

Find current directory and file's directory:

To get the full path to the directory a Python file is contained in, write this in that file:

import os dir_path = os.path.dirname(os.path.realpath(__file__))

(Note that the incantation above won't work if you've already used os.chdir() to change your current working directory, since the value of the __file__ constant is relative to the current working directory and is not changed by an os.chdir() call.)

To get the current working directory use

import os cwd = os.getcwd()

Documentation references for the modules, constants and functions used above:

The os and os.path modules.

The __file__ constant

os.path.realpath(path) (returns "the canonical path of the specified filename, eliminating any symbolic links encountered in the path")

os.path.dirname(path) (returns "the directory name of pathname path")

os.getcwd() (returns "a string representing the current working directory")

os.chdir(path) ("change the current working directory to path")

Ref: https://bit.ly/3fy0R6m