LeetCode 1827. Minimum Operations to Make the Array Increasing

class Solution {
public:
    int minOperations(vector<int>& nums) {
        int ans = 0, prev = INT_MIN;
        for (int num : nums) {
            if (num <= prev) {
                int next = prev + 1;
                ans += next - num;
                prev = next;
            } else {
                prev = num;   
            }
        }
        return ans;
    }
};