2640. Find the Score of All Prefixes of an Array

We define the conversion array conver of an array arr as follows:

• conver[i] = arr[i] + max(arr[0..i]) where max(arr[0..i]) is the maximum value of arr[j] over 0 <= j <= i.

We also define the score of an array arr as the sum of the values of the conversion array of arr.

Given a 0-indexed integer array nums of length n, return an array ans of length n where ans[i] is the score of the prefix nums[0..i].

class Solution {
public:
    vector<long long> findPrefixScore(vector<int>& nums) {
        int ma = 0;
        vector<long long> pre;
        for(auto n : nums) {
            ma = max(ma, n);
            pre.push_back((pre.size() ? pre.back() : 0) + ma + n);
        }
        return pre;
    }
};