Question

# Let me define the function I use for testing.  Don't change this cell.

def check_equal(x, y, msg=None):

    if x == y:

        if msg is None:

            print("Success")

        else:

            print(msg, ": Success")

    else:

        if msg is None:

            print("Error:")

        else:

            print("Error in", msg, ":")

        print("    Your answer was:", x)

        print("    Correct answer: ", y)

    assert x == y, "%r and %r are different" % (x, y)

## Problem 1: common word pairs

The goal is to find the set of consecutive word pairs in common between two sentences.

We will get there in steps, guiding you to the solution.

# First, notice that .split() splits a sentence according to white space, returning a list.

print("I love eating bananas".split())

# Second, recall that in Python, a[i:k] gives you the sub-list of a consisting

# of a[i], a[i+1], ..., a[k-1].

a = "I love eating bananas".split()

print(a[2:4])

### Problem 1 part 1: generating the list of consecutive words in a sentence.

You are given a sentence, with words separated by white space. You need to write a function `word_pairs` that outputs the list of consecutive words. For example, if the input is:

"I love eating bananas"
  
Then the function `word_pairs` should output:

[("I", "love"), ("love", "eating"), ("eating", "bananas")]
  
If the input sentence consists of fewer than two words, then `word_pairs` should output the empty list.
**Be careful:** the result should be a list of tuples, not a list of lists.

def word_pairs(sentence):

    # YOUR CODE HERE

# Base cases.  5 points.

check_equal(word_pairs(" "), [])

check_equal(word_pairs("woohoo"), [])

check_equal(word_pairs("I am"), [("I", "am")])

def common_word_pairs(sentence1, sentence2):

    """Returns the set of common consecutive word pairs in two sentences."""

    # YOUR CODE HERE

s1 = "I love bananas"

s2 = "I love to eat bananas"

s3 = "Nobody truly dislikes to eat bananas"

s4 = "I love to eat anything but bananas"

s5 = "I like mangos more than bananas"

check_equal(common_word_pairs(s1, s2), {("I", "love")})

check_equal(common_word_pairs(s2, s3), {("to", "eat"), ("eat", "bananas")})

check_equal(common_word_pairs(s3, s4), {("to", "eat")})

check_equal(common_word_pairs(s1, s5), set())

Answer 1

Solution:

The functions are written in python 3

Code for word_pairs()

def word_pairs(sentence):
    words=sentence.split()
    wordpairs=[]
    for i in range(0,len(words)-1):
        x=[]
        x.append(words[i])
        x.append(words[i+1])
        y=tuple(x)
        wordpairs.append(y)
    return wordpairs

Code for common_word_pairs()

def common_word_pairs(sentence1, sentence2):
    """Returns the set of common consecutive word pairs in two sentences."""
    # YOUR CODE HERE
    word_pairs1=word_pairs(sentence1)
    word_pairs2=word_pairs(sentence2)
    common = set([value for value in word_pairs1 if value in word_pairs2])
    return common 

Complete code:

def check_equal(x, y, msg=None):
    if x == y:
        if msg is None:
            print("Success")
        else:
            print(msg, ": Success")
    else:
        if msg is None:
            print("Error:")
        else:
            print("Error in", msg, ":")
        print("    Your answer was:", x)
        print("    Correct answer: ", y)
    assert x == y, "%r and %r are different" % (x, y)


def word_pairs(sentence):
    words=sentence.split()
    wordpairs=[]
    for i in range(0,len(words)-1):
        x=[]
        x.append(words[i])
        x.append(words[i+1])
        y=tuple(x)
        wordpairs.append(y)
    return wordpairs

check_equal(word_pairs(" "), [])
check_equal(word_pairs("woohoo"), [])
check_equal(word_pairs("I am"), [("I", "am")])

def common_word_pairs(sentence1, sentence2):
    """Returns the set of common consecutive word pairs in two sentences."""
    # YOUR CODE HERE
    word_pairs1=word_pairs(sentence1)
    word_pairs2=word_pairs(sentence2)
    common = set([value for value in word_pairs1 if value in word_pairs2])
    return common 

  
    
s1 = "I love bananas"
s2 = "I love to eat bananas"
s3 = "Nobody truly dislikes to eat bananas"
s4 = "I love to eat anything but bananas"
s5 = "I like mangos more than bananas"

check_equal(common_word_pairs(s1, s2), {("I", "love")})
check_equal(common_word_pairs(s2, s3), {("to", "eat"), ("eat", "bananas")})
check_equal(common_word_pairs(s3, s4), {("to", "eat")})
check_equal(common_word_pairs(s1, s5), set())

Screenshot of output: