99 Bottles of Beer/Python

Normal Code

<lang python>def sing(b, end):

   print(b or 'No more','bottle'+('s' if b-1 else ), end)

for i in range(99, 0, -1):

   sing(i, 'of beer on the wall,')
   sing(i, 'of beer,')
   print('Take one down, pass it around,')
   sing(i-1, 'of beer on the wall.\n')</lang>

Using a template

<lang python>verse = \ %i bottles of beer on the wall %i bottles of beer Take one down, pass it around %i bottles of beer on the wall

for bottles in range(99,0,-1):

   print verse % (bottles, bottles, bottles-1) </lang>

New-style template (Python 2.6)

<lang python>verse = \ {some} bottles of beer on the wall {some} bottles of beer Take one down, pass it around {less} bottles of beer on the wall

for bottles in range(99,0,-1):

   print verse.format(some=bottles, less=bottles-1) </lang>

"Clever" generator expression

<lang python>a, b, c, s = " bottles of beer", " on the wall\n", "Take one down, pass it around\n", str print "\n".join(s(x)+a+b+s(x)+a+"\n"+c+s(x-1)+a+b for x in xrange(99, 0, -1))</lang>

Enhanced "Clever" generator expression using lambda

<lang python>a = lambda n: "%u bottle%s of beer on the wall\n" % (n, "s"[n==1:]) print "\n".join(a(x)+a(x)[:-13]+"\nTake one down, pass it around\n"+a(x-1) for x in xrange(99, 0, -1))</lang>

Using a generator expression (Python 3)

<lang python>#!/usr/bin/env python3 """\ {0} {2} of beer on the wall {0} {2} of beer Take one down, pass it around {1} {3} of beer on the wall """ print("\n".join(

   __doc__.format(
       i, i - 1,
       "bottle" if i == 1 else "bottles",
       "bottle" if i - 1 == 1 else "bottles"
   ) for i in range(99, 0, -1)

), end="")</lang>

A wordy version

<lang python>ones = ( , 'one', 'two', 'three', 'four', 'five', 'six', 'seven', 'eight', 'nine' ) prefixes = ('thir', 'four', 'fif', 'six', 'seven', 'eigh', 'nine') tens = [, , 'twenty' ] teens = ['ten', 'eleven', 'twelve'] for prefix in prefixes:

   tens.append(prefix + 'ty')
   teens.append(prefix +'teen')

tens[4] = 'forty'

def number(num):

   "get the wordy version of a number"
   ten, one = divmod(num, 10)
   if ten == 0 and one == 0:
       return 'no'
   elif ten == 0:
       return ones[one]
   elif ten == 1:
       return teens[one]
   elif one == 0:
       return tens[ten]
   else:
       return "%s-%s" % (tens[ten], ones[one])

def bottles(beer):

   "our rephrase"
   return "%s bottle%s of beer" % ( 
           number(beer).capitalize(), 's' if beer > 1 else 
   )

onthewall = 'on the wall' takeonedown = 'Take one down, pass it around' for beer in range(99, 0, -1):

   print bottles(beer), onthewall
   print bottles(beer)
   print takeonedown
   print bottles(beer-1), onthewall
   print</lang>

String Formatting

<lang python>for n in xrange(99, 0, -1):

   ##  The formatting performs a conditional check on the variable.
   ##  If it formats the first open for False, and the second for True
   print n, 'bottle%s of beer on the the wall.' % ('s', )[n == 1]
   print n, 'bottle%s of beer.' % ('s', )[n == 1]
   print 'Take one down, pass it around.'
   print n - 1, 'bottle%s of beer on the wall.\n' % ('s', )[n - 1 == 1]</lang>

Python 3 f-strings and walrus operator

<lang python>bottles = 100 while (bottles:=bottles-1) != 0:

   print(f"{bottles} bottles of beer on the wall\n{bottles} bottles of beer\nTake one down, pass it around\n{bottles-1} bottles of beer on the wall\n")</lang>