#include<bits/stdc++.h>
using namespace std;
int n,a[200005],b[200005],c[200005];
int z=-2e9;
int main(){
    cin>>n;
    for(int i=1;i<=n;i++){
    	cin>>a[i];
    	b[i]=b[i-1]+a[i];
    	c[i]=min(c[i-1],b[i]);
	}
	for(int i=1;i<=n;i++){
		z=max(z,b[i]-c[i-1]);
	}
	cout<<z;
    return 0;
}