bobby_s_code.py

import json

CHRIS_Q3_ANSWER = "00000000005923C3B356E155C7E450A488BBB0C4A6DF187820954E1C35436D61"


def main():
    objs = read_parse_file('trunc_log.json')

    print "1a: %f" % q1a(objs)

    print "1a (3 decimal places only): %.3f" % q1a(objs)

    print ""

    print "1b: %f" % q1b(objs)

    print ""

    print "1c: %f" % q1c(objs)

    # If a fn returns two values you can accept them into two different variables like this:
    # If the fn only returns one value it will raise an exception
    winning_board, count = q2(objs)
    print "q2, board %d wins with %d shares" % (winning_board, count)

    # If it returns two vars and you only accept 1, it returns them as a tuple (an immutable list)
    print "shorthand print for q2: board %d wins with %d shares" % q2(objs)

    print ""

    original_hash, reversed_words_hash = q3(objs)

    print "q3 original: %s" % original_hash
    print "q3 reversed: %s" % reversed_words_hash

    if CHRIS_Q3_ANSWER == reversed_words_hash:
        print "Chris q3 was right!"
    else:
        print "Chris q3 was wrong!"


def read_parse_file(filename):
    # read the whole file, and split it on newlines
    list_of_strings = open(filename).read().split('\n')

    """
    for each string in the list of strings do one of two things
    if the string == '', then remove it from the list
    else replace the string with json.loads(string)

    The catch to remove '' is because there is a trailing newline, example:
    >>> string = 'a b c '
    >>> split(string)
    ['a', 'b', 'c', '']
    """
    list_of_objects = [json.loads(string) for string in list_of_strings if string != '']

    return list_of_objects


def get_timestamp_diff(obj):
    return obj['time'] - int(obj['timestamp'], 16)


def q1a(objs):
    return get_timestamp_diff(objs[0])


def q1b(objs):
    # python treats array indices as if the array is wrapped around in a circle
    # so, 0 is the first thing, 1 is the second, and -1 is the last
    return get_timestamp_diff(objs[-1])


def q1c(objs):
    total = 0
    for obj in objs:
        total += get_timestamp_diff(obj)
    return total


def q2(objs):
    board_counts = {}

    for obj in objs:
        bid = obj['board_id']
        if bid in board_counts:
            board_counts[bid] += 1
        else:
            board_counts[bid] = 1

    winning_board = max(board_counts)
    # returning two values:
    return winning_board, board_counts[winning_board]


def q3(objs):
    original_hash = objs[1]['hash']

    reversed_words_hash = ''

    for i in xrange(0, 8):
        start = 64 - (i + 1) * 8
        end = 64 - i * 8
        reversed_words_hash += original_hash[start:end]

    return original_hash, reversed_words_hash

main()