Homework Answers

consider the invert_dict function from Section 11.5 of your textbook. 

# From Section 11.5 of: 

# Downey, A. (2015). Think Python: How to think like a computer scientist. Needham, Massachusetts: Green Tree Press. 

def invert_dict(d):

   inverse = dict()

   for key in d:

      val = d[key]

     if val not in inverse:

        inverse[val] = [key]

     else:

        inverse[val].append(key)

   return inverse 

Modify this function so that it can invert your dictionary. In particular, the function will need to turn each of the list items into separate keys in the inverted dictionary. 

Run your modified invert_dict function on your dictionary. Print the original dictionary and the inverted one. 

Include your Python program and the output in your Learning Journal submission. 

Python Program

Write a program to print the following, Given a word W and pattern P, you need to check whether the pattern matches the given word.The word will only contain letters(can be Uppercase and Lowercase). The pattern can contain letters, ? and *.

? : Can be matched with any single letter.

* : Can be matched with any sequence of letters (including an empty sequence).

If the pattern matches with the given word, print True else False.

Sample Input1

3

Hello *l?

Hell He?ll

Hell ?*

Sample Output1

True

False

True

Sample Input1

3

Hello Hell*

Hell He*ll

Hell hell*

Sample Output1

True

True

False

Write a program that declares a structure to store BookID, price and pages of a book. It defines two structure variables and inputs values. It displays the record of most costly book.

b. Use the fraction structure from Part a, implement four-function fraction calculator. It uses

functions for each of the four arithmetic operations. They can be called fadd(), fsub(), fmul(), and

fdiv(). Each of these functions should take two arguments of type struct fraction, and return an

argument of the same type.

Search Game

A grid of letters may contain a word hidden somewhere within it. The letters of the word may be traced from the starting letter by moving a single letter at a time, up, down, left or right. For example, suppose we are looking for the word BISCUIT in this grid:

0 1 2 3

0 B I T R

1 I U A S

2 S C V W

3 D O N E

The word starts in the top left corner, continues downwards for 2 more letters, then the letter to the right followed by 2 letters moving upwards, the final letter at the right of the penultimate one.

Write a program in which we give target word and a grid of letters as input returns a list of tuples, each tuple being the row and column of the corresponding letter in the grid (numbered from 0). If the word cannot be found, output the string Not present

input1:

after

4

a b c d

f e f g

t e r r

a b i j

Output: [(0, 0),(1, 0),(2, 0),(2, 1),(2, 2)]

input2:

search

4

s e a c

r c c c

h e e e

h e e e

output: Not Present