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Python Functional Python The Lambda Lambada Reduce

python map and reduce question

I can't use map and reduce function to pass the challenge, don't know how to do...

from operator import add
from functools import reduce

prices = [
    (6.99, 5),
    (2.94, 15),
    (156.99, 2),
    (99.99, 4),
    (1.82, 102)
]

def product_sales(price):
    return price[0] * price[1]

total = reduce(map(products_sales, price), price for price in prices)  # question

1 Answer

Brendan Whiting
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Brendan Whiting
Front End Web Development Techdegree Graduate 84,703 Points

The two arguments you need to put into reduce are first the function you're using to reduce, and then the iterable you're reducing. The function is add and the iterable is what will be returned from map(product_sales, prices).

total = reduce(add, map(product_sales, prices))

thank you! I got it!