B - Maximal Continuous Rest

1. #include<cstdio>
2. #include<iostream>
3. #include<algorithm>
4. #include<string>
5. #include<cstring>
6. using namespace std;
7.  
8. int n;
9. int a[400005];
10. int maxl=0;
11.  
12. int main(){
13.     cin>>n;
14.     for(int i=1;i<=n;i++){
15.         cin>>a[i];a[i+n]=a[i];
16.     }
17.     int j;
18.     for(int i=1;i<=2*n;i++){
19.         if(a[i]==1){
20.             j=i;
21.             while(a[j+1]==1&&j<2*n)j++;
22.             maxl=max(maxl,j-i+1);
23.             i=j;
24.         }
25.     }
26.     cout<<maxl<<endl;

	
	

		}