Am 11.01.2013 17:33 schrieb [email protected]:
def factorial(n): if n<2: return 1 f = 1 while n>= 2: f *= n f -= 1 return fplease it works.
I doubt this. If you give n = 4, you run into an endless loop.
but don’t get why the return 1 and the code below.
The "if n < 2: return 1" serves to shorten the calculation process below. It is redundant, as you have a "f = 1" and a "return f" for n < 2.
The code below first sets f, which holds the result, to 1 and then multiplies it by n in each step. As the loop should contain a 'n -= 1', n decreases by 1 every step, turning it into f = n * (n-1) * (n-2) * ... * 2 and then, as n is not >= 2 any longer, stops the loop, returning f.
HTH, Thomas -- http://mail.python.org/mailman/listinfo/python-list
