21天LeetCode打卡，第18天，整数的各位积和之差
暴力：
class Solution{public:int subtractProductAndSum(intn){int n_sum =0;int n_product = 1;int rem =0;while (n != 0){rem = n % 10;n_sum += rem;n_product *= rem;n /= 10;}return n_product - n_sum;}};
暴力：
class Solution{public:int subtractProductAndSum(intn){int n_sum =0;int n_product = 1;int rem =0;while (n != 0){rem = n % 10;n_sum += rem;n_product *= rem;n /= 10;}return n_product - n_sum;}};