#include<bit/stdc++.h>
using namespace std;
long long n,x,s,p,m,a[1000100];
int main()
{
	cin >> n;
	for (int i = 1;i <= n; ++ i) cin >> a[i];
	for (int i = 1;i <= n; ++ i)
	{
		if (s >= 0) s += a[i];
		else s = a[i];
		m = max (m,s);//取最大值
	}
	cout >> m;
}

复制=CE

#include<bits/stdc++.h>
using namespace std;
long long b[100001];
int n,a[100001],res;
int main(){
	cin>>n;
	for(int i=1;i<=n;i++){
		cin>>a[i];
		if(b[i-1]>0)b[i]=b[i-1]+a[i];
		else b[i]=a[i];
	}
	for(int i=1;i<=n;i++){
		if(res<b[i])res=b[i];
	}
	cout<<res;
}