import random, string

def word_counts(f):
    result = {}
    for line in f:
        word_list = line.strip().lower().split()
        last_word = locals().get('last_word', None)

        for idx, val in enumerate(word_list):
            val = val.strip(string.punctuation)
            if last_word:
                w1 = last_word
            else:
                w1 = val

            if idx + 1 < len(word_list):
                if last_word:
                    w2 = val
                    last_word = None
                else:
                    w2 = word_list[idx + 1].strip(string.punctuation)
                if result.has_key(w1):
                    if result[w1].has_key(w2):
                        result[w1][w2] += 1
                    else:
                        result[w1].update({w2: 1})
                else:
                    result[w1] = {w2: 1}

            if idx + 1 == len(word_list):
                last_word = val

    print result

with open('input.txt') as f:
    word_counts(f)

M = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]

def transpose(mat):
    '''
    INPUT: 2 dimensional list of integers
    OUTPUT: 2 dimensional list of integers

    Return the transpose of the matrix. You may assume that the matrix is not
    empty. You can do this using a double for loop in a list comprehension.
    There is also a solution using zip.

    Example:

    >>>
    [[1, 4, 7], [2, 5, 8], [3, 6, 9]]
    '''
    # return [list(x) for x in zip(*mat)]
#     column1 = []
#     column2 = []
#     column3 = []
#     for line in mat:
#             column1.append[mat[line[0]]]
#             column2.append[mat[line[1]]]
#             column3.append[mat[line[2]]]
#
# print transpose(M)