#include <iostream>
using namespace std;

const int N = 200000;

int n;
int a[N], s[N];

int main()
{   int maxx=-20000000,c;
    scanf("%d", &n);
    for (int i = 1; i <= n; i ++ ) scanf("%d", &a[i]);

    for (int i = 1; i <= n; i ++ ) s[i] = s[i - 1] + a[i]; // 前缀和的初始化

    for(int i=1;i<=n;i++){
    	if(i==1){
    		c=a[i];
		}else{c=s[i]-s[n-1];
		}
    	
    	maxx=max(c,maxx);
	} 
        printf("%d\n",maxx); 

    return 0;
}