2535. Difference Between Element Sum and Digit Sum of an Array Time: $O(n)$ Space: $O(1)$ C++ 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22class Solution { public: int differenceOfSum(vector<int>& nums) { const int elementSum = accumulate(nums.begin(), nums.end(), 0); const int digitSum = getDigitSum(nums); return abs(elementSum - digitSum); } private: int getDigitSum(const vector<int>& nums) { int digitSum = 0; for (int num : nums) { int sum = 0; while (num > 0) { sum += num % 10; num /= 10; } digitSum += sum; } return digitSum; } };