#include <fstream>

using namespace std;
ifstream fin ("ssm.in");
ofstream fout ("ssm.out");
int v[6000001];
int main()
{
    long long n,a,s=0,smax=-200000000000000;
    fin>>n;
    for(int i=1;i<=n;++i){
        fin>>v[i];
    }
    for(int i=1;i<=n;++i){
        s+=v[i];
        smax=max(smax,s);
        if(s<0){
            s=0;
        }
    }
    fout<<smax;
    return 0;
}