3512. Minimum Operations to Make Array Sum Divisible by K

You are given an integer array nums and an integer k. You can perform the following operation any number of times:

• Select an index i and replace nums[i] with nums[i] - 1.

Return the minimum number of operations required to make the sum of the array divisible by k.

class Solution {
public:
    int minOperations(vector<int>& nums, int k) {
        int res = 0;
        for(auto& n : nums) res = (res + n) % k;
        return res;
    }
};