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# 1. Word Scores
def getWordScore(word, n):
    return (len(word) * sum(SCRABBLE_LETTER_VALUES[x] for x in word)) + (50 if len(word) == n else 0)

# Test implementation
def getFrequencyDict(aStr):
    return dict((letter, aStr.count(letter)) for letter in aStr)
	
# 2. Dealing with hands
def updateHand(hand, word):

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# 1. Paying the minimum
totalPaid = 0
for month in range(12):
    print("Month: {0:d}".format(month + 1))
    minPayment = balance * monthlyPaymentRate
    totalPaid += minPayment
    print("Minimum monthly payment: {0:.2f}".format(minPayment))
    balance -= minPayment
    balance *= (1 + (annualInterestRate / 12))
    print("Remaining balance: {0:.2f}".format(balance))

textbook

import string

# 1. Polynomials
def evaluatePoly(poly, x):
    return float(sum(b * (x ** a) for a,b in enumerate(poly)))  

# 2. Derivatives
def computeDeriv(poly):
    return [float (a * b) for a, b in enumerate(poly)][1:] or [0.0]

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from string import ascii_lowercase as lower, ascii_uppercase as upper, ascii_letters as both

# 1. Build a coder
def buildCoder(shift):
    return dict(zip(both, (lower[shift:] + lower[:shift] + upper[shift:] + upper[:shift])))

# 2. Apply the coder
def applyCoder(text, coder):
    return "".join([coder.get(letter, letter) for letter in text])

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# 3. Iterative/recursive log function
def myLog(x, b):
    a = 0
    while b ** a <= x:
        a += 1
    return a - 1

# 4. Interlace two strings iteratively
def laceStrings(s1, s2):
    shorter, longer = sorted([s1, s2], key=len)

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# 1. NewsStory
class NewsStory(object):

    def __init__(self, guid, title, subject, summary, link):
        self.guid = guid
        self.title = title
        self.subject = subject
        self.summary = summary
        self.link = link
        

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# 1. RectangularRoom
class RectangularRoom(object):
    def __init__(self, width, height):
        self.width, self.height = width, height
        self.tiles = dict(((x, y), 0) for x in range(width) for y in range(height))
    
    def cleanTileAtPosition(self, pos):
        self.tiles[(int(pos.x), int(pos.y))] += 1

    def isTileCleaned(self, m, n):

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# Problem 2: SimpleVirus and Patient
class SimpleVirus(object):

    def __init__(self, maxBirthProb, clearProb):
        self.maxBirthProb = maxBirthProb
        self.clearProb = clearProb

    def getMaxBirthProb(self):
        return self.maxBirthProb

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# Problem 4-2
class edXPerson(Person):
    nextIdNum = 0
    def __init__(self, name):
        Person.__init__(self, name)
        self.idNum = edXPerson.nextIdNum
        edXPerson.nextIdNum += 1
    def getIdNum(self):
        return self.idNum
    def __lt__(self, other):

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"""Simple unit testing functionality."""

from __future__ import print_function

def _run_function_test(function, expected, args=None, kwargs=None):
    """Check whether function returns/raises expected with supplied args."""
    if args is None:
        args = tuple()
    if kwargs is None:
        kwargs = dict()