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

He writes $*n*$ integers $*a*_{1}, *a*_{2}, ..., *a*_{*n*}$. Each of those integers can be either 0 or 1. He's allowed to do exactly one move: he chooses two indices $*i*$ and $*j*$ ($1 ≤ *i* ≤ *j* ≤ *n*$) and flips all values $*a*_{*k*}$ for which their positions are in range $[*i*, *j*]$ (that is $*i* ≤ *k* ≤ *j*$). 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.

Input

The first line of the input contains an integer $*n*$ ($1 ≤ *n* ≤ 100$). In the second line of the input there are $*n*$ integers: $*a*_{1}, *a*_{2}, ..., *a*_{*n*}$. It is guaranteed that each of those $*n*$ values is either 0 or 1.

Output

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

Note

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.