I've annotated the code fairly liberally, but if you have any questions, just ask. I'll be happy to explain anything that seems confusing.
I just realized that in an effort to make Exercise 1 less boring, I included some extra print statements that weren't required. To avoid confusion, I've replaced my first solution with a simplified one. For those who are interested, I'll post the embroidered one in a reply to this thread.
Ex 1: Write a password guessing program to keep track of how many times the user has entered the password wrong. If it is more than 3 times, print "You have been denied access." and terminate the program. If the password is correct, print "You have successfully logged in." and terminate the program.
Note: I used a baseball analogy. For strike 3, it prints what you would expect. For success, it prints "That's a homer!"
# login_simplified.py >> if exercise 1: Password guessing (login) program. # Initialize a variables to hold password, counter and message prefix. password = 'mellon' strikes = 0 # The user gets 3 tries. while strikes < 3: # Request the user's password. strike = raw_input('Enter your password: ') # Check the input against the stored password. if strike == password: # If it matches, print "\nThat's a homer!" # print success strikes = 3 # set counter to 3 to end while else: # If it doesn't match, strikes += 1 # increment the counter # Is this the last one? if strikes == 3: print "Steee-rike 3! You're out!"
Ex 2: Write a program that asks for two numbers. If the sum of the numbers is greater than 100, print "That is a big number" and terminate the program.
# sum.py >> Exercise 2: Sum two numbers; check to see if they are greater than 100. # Get the user's input and convert it. I converted to integers, # but you could convert to floats to allow for decimals if you like. num1 = int(raw_input('Enter your first number: ')) num2 = int(raw_input('Enter your second number: ')) # Add the numbers and see if their sum is greater than 100. if (num1 + num2) > 100: # If so, print the message. (Yeah, kinda boring.) print "That's a big number!"
Ex 3: Write a program that asks the user their name. If they enter your name, say "That is a nice name." If they enter "John Cleese" or "Michael Palin", tell them how you feel about them, otherwise tell them "You have a nice name."
# test_name.py >> Exercise 3: Get user name and test it against a few values. # Initialize variables to hold the comparison values. # Note: Setting all lowercase makes it easy # to normalize the user's input for cleaner comparison. my_name = 'rumplestiltskin' python1 = 'john cleese' python2 = 'michael palin' # Obtain the user's name. name = raw_input('Enter your name: ') # Check it against the stored values. # Convert user input to lower case for comparison. # This eliminates the problem of case variations. if name.lower() == my_name: print "Ooh! Can you spin straw into gold?" # Compound condition to check for 2 Pythons. elif name.lower() == python1 or name.lower() == python2: print 'And now for something completely different...' # Everyone else. else: print 'You have a nice name.'