'''
Given an integer number n, return the difference between the product of its digits and the sum of its digits.

Example 1:
Input: n = 234
Output: 15
Explanation:
Product of digits = 2 * 3 * 4 = 24
Sum of digits = 2 + 3 + 4 = 9
Result = 24 - 9 = 15

Example 2:
Input: n = 4421
Output: 21
Explanation:
Product of digits = 4 * 4 * 2 * 1 = 32
Sum of digits = 4 + 4 + 2 + 1 = 11
Result = 32 - 11 = 21

'''

#method 1

def prd_sum(n):
    p = 1
    s = 0

    digits = [int(x) for x in str(n)]
    # s = sum(digits)
    # print(s)
    for i in digits:
        s += i
        p = p * i
    print(s)
    print(p)
    print (p - s)

#method 2

def prd_sum(n):
    from functools import reduce
    from operator import mul
    digits = [int(x) for x in str(n)]
    print(reduce(mul, digits) - sum(digits))

prd_sum(4421)