B'You are given an array a_1, a_2, ldots, a_n of n integers. Consider S as a set of segments satisfying the following conditions. The length of the segment [x, y] is defined as y-x+1 . f(S) is defined as the sum of the lengths of every element in S . In a formal way, f(S) = sum_{[x, y] in S} (y - x + 1) . Note that if S is empty, f(S) is 0 . What is the maximum f(S) among all possible S ? The first line contains one integer n ( 1 <= q n <= q 2 cdot 10^5 ). The next line is followed by n integers a_1, a_2, ldots, a_n ( -10^9 <= q a_i <= q 10^9 ). Print a single integer, the maximum f(S) among every possible S . In the first example, S= {[1, 2], [4, 5] } can be a possible S because a_1+a_2=0 and a_4+a_5=1 . S= {[1, 4] } can also be a possible solution. Since there does not exist any S that satisfies f(S) > 4 , the answer is 4 . In the second example, S= {[1, 9] } is the only set that satisfies f(S)=9 . Since every possible S satisfies f(S) <= q 9 , the answer is 9 . In the third example, S can only be an empty set, so the answer is 0 . '...