电影院选座

#include<bits/stdc++.h>
#define rep(i,a,n) for(int i=a;i<=n;i++)
#define per(i,n,a) for(int i=n;i>=a;i--)
using namespace std;
typedef long long ll;
const int maxn=5010;//数组所开最大值
const int mod=1e9+7;//模
const int inf=0x3f3f3f3f;//无穷大
int main()
{

    int nums[20010];
    int n = 0;
    char c;
    while((c=getchar())!='\n')
    {
        if(c>='0'&&c<='9')
        {
            ungetc(c,stdin);
            cin>>nums[n++];
        }
    }
    int cnt = 0;
    int res = 0;
    int s = 0;
    int e = 0;
    for(int i = 0; i < n; i ++)
    {   s = min(i,s);
        if(nums[i] == 0)
        {
            cnt ++;
        }
        else
        {
            e = i;
            if(nums[s] == 1 && nums[e] == 1){
               if(cnt >= res){
                   ///0 0 1 0 0 1 0 1 1 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 1 0
                 int temp = cnt + 2;
               if(temp % 2 == 0)
                    temp = temp / 2 -1;
               else
                    temp = temp / 2;
                 res = max(res,temp);
               }
            }
            else{
                res = max(res,cnt);
            }
            cnt = 0;
            s = i;
        }
    }
    //0 0 0 1 0 0 0 1 0 0 0 0
    res = max(res,cnt);
    cout <<res << endl;

}