warm-up 1.py

#!/usr/bin/env python2
# -*- coding: utf-8 -*-
"""
Created on Mon Mar 11 13:44:42 2019

@author: YaoJunyan
"""

'''
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.


sleep_in(False, False) → True
sleep_in(True, False) → False
sleep_in(False, True) → True

'''
def sleep_in(weekday, vacation):
  if weekday ==False or vacation ==True:
    return True
  else:
    return False


'''
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.


monkey_trouble(True, True) → True
monkey_trouble(False, False) → True
monkey_trouble(True, False) → False

'''
def monkey_trouble(a_smile, b_smile):
  if a_smile and b_smile:
    return True
  elif a_smile ==False and b_smile==False:
    return True
  else:
    return False


'''
sum_double


Given two int values, return their sum. Unless the two values are the same, then return double their sum.


sum_double(1, 2) → 3
sum_double(3, 2) → 5
sum_double(2, 2) → 8

'''
def sum_double(a, b):
  if a== b:
    return (a+b)*2
  else:
    return a+b

'''
diff21

Given an int n, return the absolute difference between n and 21, except return double the absolute difference if n is over 21.


diff21(19) → 2
diff21(10) → 11
diff21(21) → 0
'''
def diff21(n):
  if n<21:
    return 21-n
  else:
    return (n-21)*2

'''
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.


parrot_trouble(True, 6) → True
parrot_trouble(True, 7) → False
parrot_trouble(False, 6) → False
'''
def parrot_trouble(talking, hour):
  if talking ==True and (hour<7 or hour >20):
    return True
  else:
    return False

'''
makes10

Given 2 ints, a and b, return True if one if them is 10 or if their sum is 10.


makes10(9, 10) → True
makes10(9, 9) → False
makes10(1, 9) → True
'''

def makes10(a, b):
  if a==10 or b==10 or (a+b)==10:
    return True
  else:
    return False

'''
near_hundred
Given an int n, return True if it is within 10 of 100 or 200. Note: abs(num) computes the absolute value of a number.


near_hundred(93) → True
near_hundred(90) → True
near_hundred(89) → False
'''
def near_hundred(n):
  if abs(100-n)<=10 or abs(200-n)<=10:
    return True
  else:
    return False

'''
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.


pos_neg(1, -1, False) → True
pos_neg(-1, 1, False) → True
pos_neg(-4, -5, True) → True

'''
def pos_neg(a, b, negative):
  if negative ==True:
    if a<0 and b<0:
      return True
    else:
      return False
  elif a*b<0:
    return True
  else:
    return False
    

'''
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.


not_string('candy') → 'not candy'
not_string('x') → 'not x'
not_string('not bad') → 'not bad'
'''
def not_string(str):
  if str.startswith('not'):
    return str
  else:
    return '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. The value of n will be a valid index of a char in the original string (i.e. n will be in the range 0..len(str)-1 inclusive).


missing_char('kitten', 1) → 'ktten'
missing_char('kitten', 0) → 'itten'
missing_char('kitten', 4) → 'kittn'
'''
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.


front_back('code') → 'eodc'
front_back('a') → 'a'
front_back('ab') → 'ba'
'''
def front_back(str):
  if len(str)>=1:
    if len(str)==1:
      return str
    else:
      return str[-1]+str[1:-1]+str[0]
  else:
    return 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.


front3('Java') → 'JavJavJav'
front3('Chocolate') → 'ChoChoCho'
front3('abc') → 'abcabcabc'
'''
def front3(str):
  if len(str)>=3:
    return str[0:3]*3
  else:
    return str*3