2500 - 2599
2535 - Difference Between Element Sum and Digit Sum of an Array (Easy)
Problem Link
https://leetcode.com/problems/difference-between-element-sum-and-digit-sum-of-an-array/
Problem Statement
You are given a positive integer array nums.
- The element sum is the sum of all the elements in
nums. - The digit sum is the sum of all the digits (not necessarily distinct) that appear in
nums.
Return the absolute difference between the element sum and digit sum ofnums.
Note that the absolute difference between two integers x and y is defined as |x - y|.
Example 1:
Input: nums = [1,15,6,3]
Output: 9
Explanation:
The element sum of nums is 1 + 15 + 6 + 3 = 25.
The digit sum of nums is 1 + 1 + 5 + 6 + 3 = 16.
The absolute difference between the element sum and digit sum is |25 - 16| = 9.Example 2:
Input: nums = [1,2,3,4]
Output: 0
Explanation:
The element sum of nums is 1 + 2 + 3 + 4 = 10.
The digit sum of nums is 1 + 2 + 3 + 4 = 10.
The absolute difference between the element sum and digit sum is |10 - 10| = 0.Constraints:
1 <= nums.length <= 20001 <= nums[i] <= 2000
Approach 1: Straight Forward
class Solution {
public:
int f(int x) {
int res = 0;
while (x) {
// get the last digit
res += x % 10;
// divide by 10 to remove the last digit
x /= 10;
}
return res;
}
int differenceOfSum(vector<int>& nums) {
int es = 0, ds = 0;
for (auto x : nums) {
// calculate element sum
es += x;
// calculate digit sum
ds += f(x);
}
// return the absolute difference between the element sum and digit sum of nums.
return abs(es - ds);
}
};