#include<bits/stdc++.h>
using namespace std;
#define int long long
const int N=2e5+10;
int a[N],mn;
signed main()
{
	int n;scanf("%lld",&n);
	for(int i=1;i<=n;i++)
	{
		scanf("%lld",&a[i]);
		a[i]+=a[i-1];
		mn=min(mn,a[i]);
	}
	printf("%lld\n",a[n]-mn);
	return 0;
}