def acronym(phrase):
    a = ''
    for word in phrase.split():
        a += word[0]
    return a.upper()

def acronym(phrase):
    return ''.join([word[0] for word in phrase.split()]).upper()

def threshold(dailyGains, goal):
  day = 0
  subtotal = 0.0
  while subtotal < goal and day < len(dailyGains):
    subtotal += dailyGains[day]
    day += 1
  if subtotal < goal:
    day = 0              # goal was unachievable
  return day

def cheerlead(word):
  for letter in word.upper():
    print 'Gimme',
    if letter in 'AEFHILMNORSX':
      print 'an',
    else:
      print 'a ',
    print letter
  print "What's that spell?"
  print word

def sliding(word, num=3):
  if not isinstance(word, str):
    raise TypeError('word must be a string')
  if not isinstance(num, int):
    raise TypeError('num must be an integer')
  if num <= 0:
    raise ValueError('num must be positive')
  if num > len(word):
    raise ValueError('num cannot be greater than the word length')
  for i in range(len(word) + 1 - num):
    print ' ' * i + word[i:i+num]

def toDecimal(string, base):
  place = 1
  total = 0
  original = string[ : :-1]   # reverse for convenience
  for symbol in original:
    if symbol.isdigit():
      value = int(symbol)
    else:
      value = 10 + ord(symbol) - ord('A')
    total += value * place
    place *= base
  return total