Package for this problem was not updated by the problem writer or Codeforces administration after we’ve upgraded the judging servers. To adjust the time limit constraint, solution execution time will be multiplied by 2. For example, if your solution works for 400 ms on judging servers, then value 800 ms will be displayed and used to determine the verdict.

Virtual contest is a way to take part in past contest, as close as possible to participation on time. It is supported only ICPC mode for virtual contests.
If you've seen these problems, a virtual contest is not for you - solve these problems in the archive.
If you just want to solve some problem from a contest, a virtual contest is not for you - solve this problem in the archive.
Never use someone else's code, read the tutorials or communicate with other person during a virtual contest.

No tag edit access

A. Flipping Game

time limit per test

1 secondmemory limit per test

256 megabytesinput

standard inputoutput

standard outputIahub 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.

Examples

Input

5

1 0 0 1 0

Output

4

Input

4

1 0 0 1

Output

4

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.

Codeforces (c) Copyright 2010-2020 Mike Mirzayanov

The only programming contests Web 2.0 platform

Server time: Aug/06/2020 04:35:57 (i1).

Desktop version, switch to mobile version.

Supported by

User lists

Name |
---|