'''
    basics.py -- examples of some of the simplest language constructs

    Jeff Ondich, 24 October 2006
    Tianna Avery, November 2018, updated for Python 3

    Read through the code and predict its output.  Keep an eye out for
    weird stuff (e.g. "what is that // operator for?").  Also, there's
    one line that crashes this program--read the resulting error message,
    fix the program, and move on.
'''

print('=============== Arithmetic ==============')
a = 7
b = 3
c = 3.0
print('a =', a)
print('b =', b)
print('c =', c)
print('a + b =', a + b)
print('a * b =', a * b)
print('a // b =', a // b)
print('a / b =', a / b)
print('a / c =', a / c)
print('float(a) / float(b) =', float(a) / float(b))
print('float(a) // float(b) =', float(a) // float(b))
print('a % b =', a % b)
print()

print('=============== Literal strings ==============')
print('this string is surrounded by single quotes and has "double quotes" in it')
print("this string is surrounded by double quotes, and won't squawk at an apostrophe")
print('this string includes some\n\nnewline characters')
print()

print('=============== Formatted strings ==============')
number = 23
animal = 'goat'
print('this string has an interpolated integer ({0})'.format(number))
print('this string has an interpolated string ({0})'.format(animal))
print('this string has both ({0} and {1})'.format(number, animal))
print(f'You can use "f" strings to include variables directly in the formatted string: {animal} and {number}')
print('e.g. {{0:.2f}} restricts a float to two decimal places: {0:.2f}'.format(7.0/3.0))
print()

print('=============== Simple input ==============')
name = input('Who are you? ')
print('Hi', name, '.  Nice to meet you.')
print()
print('I am going to ask you for a number now, and then the line after that will crash. Why, and how can you fix it?')
a = input('Number, please: ')
print(a, 'squared = ', a*a)
print()

print('=============== if-elif-else ==============')
animal = input('Animal, please: ')

if animal == 'goat':
    print('billy or nanny?')
elif animal == 'octopus':
    print('the plural is octopi')
    print('but octopuses is becoming more accepted')
    print('octopodes is correct, too, but really, who would ever use that?')
    print('(did you notice that indentation is relevant in Python, and braces are absent?)')
else:
    print('I like %ss' % animal)
    print("(don't forget the colon after the else)")
    print('(why did I use double quotes on that last string?)')

print()

print('=============== while loops ==============')
n = 10
while n > 0:
    print(n)
    n = n - 1

print('Note that Python lacks -- and ++ operators!')
print()

print('=============== boolean operators ==============')
n = int(input('Number, please: '))

if n < -1000 or n > 1000:
    print("That's a large-magnitude number")
elif n >= 0 and n < 700:
    print('Positive, but not huge')
elif not (n == 729):
    print('Boring number')
else:
    print('I like 729')