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Exercise 0: Playing with chr and ord

Show the output that would be generated by the following program fragment:

msg = ""
for ch in "banana":
    mystery = chr(ord(ch) + 4)
    print(mystery)

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Exercise 1: Basic List operations

For this exercise, we’ll use the following statements:

numbers = [3, 1, 4, 1, 5]
words = ["apple", "banana", "cat", "dog", "elephant"]

Predict the result of evaluating each of the following list expressions.

a) numbers + words

b) 2 * numbers + words

c) numbers[-1]

d) words[1:4]

e) words[1] + words[2]

f) len(numbers)

g) for word in words:
       print(word[:3])

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Exercise 2: For-loop Patterns

Write a for loop using the variables numbers and words to generate each output. Think about whether you need the element and/or its index for each loop.

numbers = [3, 1, 4, 1, 5]
words = ["apple", "banana", "cat", "dog", "elephant"]

a) ae
   ba
   ct
   dg
   et

b) 0 apple
   1 banana
   2 cat
   3 dog
   4 elephant

c) 3
    1
     4
      1
       5

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Exercise 3: Going backwards

Exercise 3a: building a new result

Write a program to print a sequence of words in reverse order. You cannot use slicing or the existing reverse list method. (Hint: you should use split to turn the provided string into a list, and use the accumulator pattern to build the resulting list in reversed order.)

Here is an example interaction:

Please enter a sequence of words, separated by spaces: apple banana cat dog elephant fish

The sequence reversed:
fish elephant dog cat banana apple

Just for fun, see if you can build the resulting reversed list using a single slicing operation.

Exercise 3b: reversing in place

Now, instead of building up a new reversed result, reverse the provided list in-place, i.e. by modifying the original list, without using any additional variables. (Hint: remember that Python allows for simultaneous assignment.)

Here is an example interaction:

>>> mylist = ["apple", "banana", "cat"]
>>> mylist
['apple', 'banana', 'cat']
>>> YOUR CODE HERE
>>> mylist
['cat', 'banana', 'apple']

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