warmup-1.py

"""
sleep_in
The parameter weekday is True if it is a weekday,
and the parameter vacation is True if we are on vacation.
We sleep in if it is not a weekday or we're on vacation.
Return True if we sleep in.
"""
def sleep_in(weekday, vacation):
  return vacation or not weekday

"""
monkey_trouble
We have two monkeys, a and b, and the parameters
a_smile and b_smile indicate if each is smiling.
We are in trouble if they are both smiling or if neither of them is smiling.
Return True if we are in trouble.
"""
def monkey_trouble(a_smile, b_smile):
  return a_smile == b_smile

"""
sum_double
Given two int values, return their sum.
Unless the two values are the same, then return double their sum.
"""
def sum_double(a, b):
  return (a + b) if a != b else (a + b)*2

"""
diff21
Given an int n, return the absolute difference between n and 21,
except return double the absolute difference if n is over 21.
"""
def diff21(n):
  return abs(n - 21) if n <= 21 else 2*abs(n - 21)

"""
parrot_trouble
We have a loud talking parrot.
The "hour" parameter is the current hour time in the range 0..23.
We are in trouble if the parrot is talking and the hour is before 7 or after 20.
Return True if we are in trouble.
"""
def parrot_trouble(talking, hour):
  return talking and (hour < 7 or hour > 20)

"""
makes10
Given 2 ints, a and b, return True if one if them is 10 or if their sum is 10.
"""
def makes10(a, b):
  return a + b == 10 or a == 10 or b == 10

"""
near_hundred
Given an int n, return True if it is within 10 of 100 or 200.
"""
def near_hundred(n):
  return n in range(90, 111) or n in range(190, 211)

"""
pos_neg
Given 2 int values, return True if one is negative and one is positive.
Except if the parameter "negative" is True, then return True only if both are negative.
"""
def pos_neg(a, b, negative):
  if negative:
    return a < 0 and b < 0
  else:
    return (a < 0 and b > 0) or (a > 0 and b < 0)

"""
not_string
Given a string, return a new string where "not " has been added to the front.
However, if the string already begins with "not", return the string unchanged.
"""
def not_string(str):
  return str if str[:3] == "not" else ("not "+str)

"""
missing_char
Given a non-empty string and an int n, return a new string where the char
at index n has been removed.
"""
def missing_char(str, n):
  return (str[:n] + str[n+1:])

"""
front_back
Given a string, return a new string where the first and last chars have been exchanged."""
def front_back(str):
  return str[-1] + str[1:-1] + str[0] if len(str) >= 2 else str

"""
front3
Given a string, we'll say that the front is the first 3 chars of the string.
If the string length is less than 3, the front is whatever is there.
Return a new string which is 3 copies of the front.
"""
def front3(str):
  return 3*str[:3] if len(str) > 2 else 3*str