LeetCode 396. Rotate Function

public class Solution {
public int maxRotateFunction(int[] A) {
int l = A.length;
if (l == 0) return 0;
int first = 0;
int offset = 0;
int sup = 0;
for (int i = 0; i < l; i++) {
first += i * A[i];
offset += A[i];
}
int max = first;
for (int i = 0; i < l - 1; i++) {
sup += l * A[i];
int f = first - offset * (i + 1) + sup;
max = max > f ? max : f;
}
return max;
}
}