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Sohail Mirza
Python Web Development Techdegree Student 5,158 PointsNeed help with one line of the code
I don't understand why product =1 , why isnt it product = 0. What is the logic behind it
def multiply(*args):
product = 1
for arg in args:
product *= arg
return product
2 Answers
Chris Freeman
Treehouse Moderator 68,423 PointsIn arithmetic, 1 is the multiplicative identity, whereas, 0 is the additive identity:
n = 1 * n
n = 0 + n
That is,
5 * 4 * 3 == 1 * 5 * 4 * 3
So, initializing the product to 1 will allow the loop to be seeded with a neutral starting value.
You could also initialize product to the first item in *args then loop over the remaining args:
product = args[0]
for arg in args[1:]:
product *= arg
return product
KRIS NIKOLAISEN
54,967 PointsBecause you are multiplying with product *= arg, the equivalent to product = product*arg. If product were initialized to 0 the result would always be 0.