Iahub got bored, so he invented a game to be played on paper.

He writes n integers a1,a2,...,an. Each of those integers can be either 0 or 1. He's allowed to do exactly one move: he chooses two indices i and j (1 \le i \le j \le n) and flips all values ak for which their positions are in range [i,j] (that is i \le k \le j). Flip the value of x means to apply operation x=1 - x.

The goal of the game is that after exactly one move to obtain the maximum number of ones. Write a program to solve the little game of Iahub.

The first line of the input contains an integer n (1 \le n \le 100). In the second line of the input there are n integers: a1,a2,...,an. It is guaranteed that each of those n values is either 0 or 1.

Print an integer - the maximal number of 1s that can be obtained after exactly one move.

In the first case, flip the segment from 2 to 5 (i=2,j=5). That flip changes the sequence, it becomes: [1 1 1 0 1]. So, it contains four ones. There is no way to make the whole sequence equal to [1 1 1 1 1].

In the second case, flipping only the second and the third element (i=2,j=3) will turn all numbers into 1.