#Newbie programmer
def factorial(x):
      if x == 0:
          return 1
      else:
          return x * factorial(x - 1)
print factorial(6)

#First year programmer, studied Pascal
def factorial(x):
      result = 1
      i = 2
      while i <= x:
          result = result * i
          i = i + 1
      return result
print factorial(6)

#First year programmer, studied C
def fact(x): #{
      result = i = 1;
      while (i <= x): #{
          result *= i;
          i += 1;
      #}
      return result;
#}
print(fact(6))

#First year programmer, SICP
@tailcall
def fact(x, acc=1):
      if (x > 1): return (fact((x - 1), (acc * x)))
      else:       return acc
print(fact(6))

#First year programmer, Python
def Factorial(x):
      res = 1
      for i in xrange(2, x + 1):
          res *= i
      return res
print Factorial(6)

#Lazy Python programmer
def fact(x):
      return x > 1 and x * fact(x - 1) or 1
print fact(6)

#Lazier Python programmer
f = lambda x: x and x * f(x - 1) or 1
print f(6)

#Python expert programmer
import operator as op
import functional as f
fact = lambda x: f.foldl(op.mul, 1, xrange(2, x + 1))
print fact(6)

#Python hacker
import sys
@tailcall
def fact(x, acc=1):
      if x: return fact(x.__sub__(1), acc.__mul__(x))
      return acc
sys.stdout.write(str(fact(6)) + '\n')

#EXPERT PROGRAMMER
import c_math
fact = c_math.fact
print fact(6)

#ENGLISH EXPERT PROGRAMMER
import c_maths
fact = c_maths.fact
print fact(6)

#Web designer
def factorial(x):
      #-------------------------------------------------
      #--- Code snippet from The Math Vault          ---
      #--- Calculate factorial (C) Arthur Smith 1999 ---
      #-------------------------------------------------
      result = str(1)
      i = 1 #Thanks Adam
      while i <= x:
          #result = result * i  #It's faster to use *=
          #result = str(result * result + i)
             #result = int(result *= i) #??????
          result str(int(result) * i)
          #result = int(str(result) * i)
          i = i + 1
      return result
print factorial(6)

#Unix programmer
import os
def fact(x):
      os.system('factorial ' + str(x))
fact(6)

#Windows programmer
NULL = None
def CalculateAndPrintFactorialEx(dwNumber,
                     hOutputDevice,
                     lpLparam,
                     lpWparam,
                     lpsscSecurity,
                     *dwReserved):
      if lpsscSecurity != NULL:
          return NULL #Not implemented
      dwResult = dwCounter = 1
      while dwCounter <= dwNumber:
          dwResult *= dwCounter
          dwCounter += 1
      hOutputDevice.write(str(dwResult))
      hOutputDevice.write('\n')
      return 1
import sys
CalculateAndPrintFactorialEx(6, sys.stdout, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL)

#Enterprise programmer
def new(cls, *args, **kwargs):
      return cls(*args, **kwargs)

class Number(object):
      pass

class IntegralNumber(int, Number):
      def toInt(self):
          return new (int, self)

class InternalBase(object):
      def __init__(self, base):
          self.base = base.toInt()

      def getBase(self):
          return new (IntegralNumber, self.base)

class MathematicsSystem(object):
      def __init__(self, ibase):
          Abstract

      @classmethod
      def getInstance(cls, ibase):
          try:
              cls.__instance
          except AttributeError:
              cls.__instance = new (cls, ibase)
          return cls.__instance

class StandardMathematicsSystem(MathematicsSystem):
      def __init__(self, ibase):
          if ibase.getBase() != new (IntegralNumber, 2):
              raise NotImplementedError
          self.base = ibase.getBase()

      def calculateFactorial(self, target):
          result = new (IntegralNumber, 1)
          i = new (IntegralNumber, 2)
          while i <= target:
              result = result * i
              i = i + new (IntegralNumber, 1)
          return result

print StandardMathematicsSystem.getInstance(new (InternalBase, new (IntegralNumber, 2))).calculateFactorial(new (IntegralNumber, 6))