Leetcode 1281. Subtract the Product and Sum of Digits of an Integer

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　 Product of digits = 2 _ 3 _ 4 = 24

Programming Skills I Easy

Description

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

• 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

• Product of digits = 4 _ 4 _ 2 * 1 = 32
  Sum of digits = 4 + 4 + 2 + 1 = 11
  Result = 32 - 11 = 21

Constraints:

• 1 <= n <= 10^5

Solution

class Solution:
    # Iteration
    # Time Complexity: BigO(N)
    # Space Complexity: BigO(1)
    def subtractProductAndSum(self, n: int) -> int:
        pod, sod = 1, 0
        for num in str(n):
            pod *= int(num)
            sod += int(num)
        return pod - sod

• functools.reduce(function, iterable[, initializer]): reduce((lambda x, y: x * y), map(int, str(n)))

/**
 * Iteration
 * Time Complexity: BigO(N)
 * Space Complexity: BigO(1)
 */
function subtractProductAndSum(n: number): number {
  const nStr = n.toString();
  let pod = 1;
  let sod = 0;
  for (const ns of nStr) {
    pod *= Number(ns);
    sod += Number(ns);
  }
  return pod - sod;
}

• Array.prototype.reduce(): reduce((acc, cur) => (acc *= Number(cur)), 1)