40分求调

#include<bits/stdc++.h>
using namespace std;
long long n,a[100005],s[100005];
int main(){	
	cin>>n;
	for(int i=1;i<=n;i++){
		cin>>a[i]; 
		s[i]=s[i-1]+a[i];
	}
	long long ans=a[1],minn=0;
	for(int i=1;i<=n;i++){
		ans=max(ans,s[i]-minn);
		minn=min(minn,s[i]);
	}
	cout<<ans;
	return 0;
}