Compsci 101, Fall 2014, Classwork Nov 4, 2014

Solve these problems and enter them in the google forms for today.

Answers to problems 1 and 2 in www.bit.ly/101fall14-1104-01

Problem 1:

What is the resulting output? Think, don't cut and paste!

d = {'duke':30, 'unc':50, 'ncsu':40} print "d.values()", d.values() print "d.keys()", d.keys() d['duke'] = 80 d.update({'ecu':40, 'uncc':70}) print "d.values()", d.values()

Problem 2:

Assume d is the resulting dictionary from above. What is the difference between these 3? print "d.items()", d.items() print "d.iteritems()", d.iteritems() print "d", d

Answers to problems 3 and 4 in www.bit.ly/101fall14-1104-02

Problem 3:

Using the dictionary from above, write Python code to determine how many schools have more than 40 attendees?

Problem 4:

Using the dictionary from above, which schools have more than 40 attendees?

Answer to problem 5 in www.bit.ly/101fall14-1104-03

Problem 5:

Part A: Create a new dictionary from d that can easily answer questions such as, which schools have X attendees.

Part B: Create a new dictionary from d mapping groups of 50 attendees, group 0-49 together, 50-99, etc.

Answer to problem 6 in www.bit.ly/101fall14-1104-04

Problem 6:

Create a dictionary of popular song titles and how many times each song is 1st place, 2cd place, 3rd place... see songtitles.py

Answer to problem 7 in www.bit.ly/101fall14-1104-05

Problem 7:

Discuss with others an algorithm for solving the APT EmailsCourse. Write in words (not code) your algorithm.