import sys


def MaxNum(n, lis):
    k = [0 for _ in range(n)]
    k[0] = lis[0]
    for i in range(1, n):
        k[i] = max(lis[i],k[i-1] + lis[i]) 
    return max(k)

if __name__ == "__main__":
    n = int(input())
    l = []
    for _ in range(n):
        l.append(int(input()))
    ans = MaxNum(n,l)
    print(ans)

最简单的动归,不解释