#include<bits/stdc++.h>
using namespace std;

const int N=1e6+10;
const int INF=1e8+10;
long long a[N],maxn[N],minn[N];
int main()
{
    int n,x;
    long long mint=INF,ans=-INF;
    scanf("%d",&n);
    for(int i=1;i<=n;i++)
    {
        scanf("%d",&x);
        a[i]=a[i-1]+x;
        if(a[i]<mint)mint=a[i];
        minn[i]=mint;
        ans=max(ans,a[i]-minn[i-1]);
    }
    printf("%lld",ans);
    return 0;
}