Strings - Solutions
===================

.. contents:: :local:

.. _pwp-str-ex1:

Exercise 1
----------


Solution
^^^^^^^^

.. interactive_code_block:: 
   :caption: A script abbreviating a term
   
   term = 'Light Amplification by Stimulated Emission of Radiation'

   # Create a variable to be able to add the roman symbols
   abbreviated_term = ''
   #Iterate over the characters in the term
   for character in term:
       # If the character is uppercase...
       if character.isupper():
           # ...add it to the abbreviation
           abbreviated_term += character

   print(abbreviated_term)


Shorter solution using a list comprehension
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Simple ``for ... in ...:`` loops can sometimes be replaced by `list comprehensions <list comprehension>`__.

.. interactive_code_block:: 
   :caption: A script abbreviating a term
   
   term = 'Light Amplification by Stimulated Emission of Radiation'

   # Iterate over the characters in the term using a list comprehension
   abbreviated_term = ''.join([character for character in term if character.isupper()])
   print(abbreviated_term)

.. _pwp-str-ex2:

Exercise 2
----------


Solution
^^^^^^^^

.. interactive_code_block:: 
   :caption: A script to reverse a string character by character

   string = 'A man, a plan, a canal - Panama!'

   reversed_string = string[::-1]
   
   print(reversed_string)

.. _pwp-str-ex3:

Exercise 3
----------


Solution
^^^^^^^^

.. interactive_code_block:: A script to reverse a string word by word

   string = 'Are you as excited as i am?'

   # Use a single space as a sperator
   separator = ' '
   # Split the string to a list of words
   list_of_words = string.split(separator)
   # Reverse that list of words
   list_of_words.reverse()
   # Join the list of words back together to a string using the seperator
   string = separator.join(list_of_words)

   print(string)

.. CANNOT BE CONDENSED
   Condensed solution using less variables
   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

   .. interactive_code_block:: A script to reverse a string word by word

      string = 'Are you as excited as i am?'

      # The same script as before in only two lines
      list_of_words = string.split()
      string = ' '.join(list_of_words.reverse())

      print(string)