codeforces 192a

link: http://codeforces.com/contest/330/problem/A brute force. 

/*
ID: zypz4571
LANG: C++
TASK: 191a.cpp
 */

#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <cctype>
#include <algorithm>
#include <queue>
#include <set>
#include <queue>
#include <list>
#include <map>
#define INF 0x3f3f3f3f
#define mid int m=(l+r)/2
using namespace std;
int a[102];
int main ( int argc, char *argv[] )
{
#ifndef ONLINE_JUDGE
    freopen("191a.in", "r", stdin);
#endif
    int n, n1=0, cnt=0, Max=0; scanf("%d", &n);
    for (int i=0; i<n; ++i){
        scanf("%d",a+i); if(a[i]) n1++;
    }
    if (n1 == n) Max = n1-1;
    else 
    {
        Max = n1;
        for (int i=0; i<n; ++i) {
            for (int j=0; j<n; ++j) {
                cnt = n1;
                for (int k=i; k<=j; ++k) {
                    if (!a[k]) cnt++; else cnt--;
                }
                if (cnt > Max) Max = cnt;
            }
        }
    }
    printf("%d\n", Max);

        return EXIT_SUCCESS;
}                /* ----------  end of function main  ---------- */

It is so easy. However, I got a WA at first. sad……