diff -r 88a01948450d -r d33698326409 manipulating_lists/questions.rst --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/manipulating_lists/questions.rst Wed Dec 01 16:51:35 2010 +0530 @@ -0,0 +1,72 @@ +Objective Questions +------------------- + +.. A mininum of 8 questions here (along with answers) + +1. Given the list primes, ``primes = [2, 3, 5, 7, 11, 13, 17, 19, 23, + 29]``, How do you obtain the last 4 primes? + + Answer: primes[-4:] + +#. Given the list primes, ``primes = [2, 3, 5, 7, 11, 13, 17, 19, 23, + 29]``, What is the output of ``primes[::5]``? + + Answer: ``[2, 13]`` + +#. Given a list, p, of unknown length, obtain the first 3 (or all, if + there are fewer) characters of it. + + Answer: p[:3] + +#. The method ``reverse`` reverses a list in-place. True or False? + + Answer: True + +#. ``reversed`` function reverses a list in-place. True or False? + + Answer: False + +#. Given the list ``p = [1, 2, 3]``. p[4] produces an IndexError. True + or False? + + Answer: True + +#. Given the list ``p = [1, 2, 3]``. p[:4] produces an IndexError. True + or False? + + Answer: False + +#. Given the list primes, ``primes = [2, 3, 5, 7, 11]``, What is the + output of ``primes[::-1]``? + + Answer: [11, 7, 5, 3, 2] + +#. Given the list primes, ``primes = [2, 3, 5, 7, 11]``, What is the + output of ``primes[::-3]``? + + Answer: [11, 3] + + +Larger Questions +---------------- + +.. A minimum of 2 questions here (along with answers) + +#. Given a list p. Append it's reverse to itself. + + Answer:: + + p = p + reversed(p) + + +#. Marks is a list containing the roll numbers of students followed by + marks. [This is not a recommended way to hold the marks details, + but the teacher knows only so much Python!] Now she wants to get + the average of the marks. Help her do it. + + Answer:: + + marks = [1, 9, 2, 8, 3, 3, 4, 10, 5, 2] + average = sum(marks[1::2])/len(marks[1::2]) + +