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Python Functional Python The Lambda Lambada Reduce

Posted by John Shockey
John Shockey
45,061 Points

[SOLVED] Completely stuck on task 4 of 4

I'm lost and don't know where to go from here.

prices.py 
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(prices):
    return prices[0] * prices[1]

total = map(product_sales, prices) + reduce(product_sales, [ ])

1 Answer

Steven Parker
Steven Parker
220,634 Points
Steven Parker
Steven Parker
220,634 Points

You're close...

You figured out the part about using map to generate the totals: map(product_sales, prices) :white_check_mark:

Remember that reduce applies a function to a list, and you're creating the list with map. And you imported the add function already, so you just need to pass the function and the list to reduce:

    total = reduce( add, map(product_sales, prices) )
John Shockey
John Shockey
45,061 Points

Ahhh gotcha. Thanks!