String operations
=================

#. Which are the values of variables ``a``, ``b``, ``c``, ``d``,
   ``l``, ``e``, ``f``, ``g`` after the execution of these lines of
   code. Guess it manually and then check your answer using a Python
   shell.

   .. code:: python

    >>> s='abcdef'
    >>> a=s[3]
    >>> b=s[5] 
    >>> c=s[0] 
    >>> l=len(s)
    >>> d=s[l-1]
    >>> e=s[l-4]
    >>> f=s[-1]
    >>> g=s[-4]

#. From the initialization of string variable s in the first line,
   evaluate the following expressions. Guess it manually and then check
   your answer using a Python shell.

   .. code:: python

    >>> s = 'daydreamer'
    >>> s[2]
    >>> s[-1]
    >>> s[:3]
    >>> s[-7:]
    >>> 'dream' in s
    >>> 'dreams' in s
    >>> s[-3::-5] + ' ' + s[1::3]