import sys
"""
用前缀和做,时间复杂度为o(n^2),在本题中会超时
下面是动态规划解决,时间复杂度为o(n),解决超时问题
n = int(input())
l = list(map(int, input().split()))
for i in range(1, len(l)):
l[i] = l[i - 1] + l[i]
if n == 1:
print(l[0])
else:
dp = [l[0]]
for i in range(1, len(l)):
dp.append(l[i])
for j in range(i):
dp.append(l[i] - l[j])
print(max(dp))
"""
n = int(input())
l = list(map(int, input().split()))
# 创建初始化值为负无穷大的数组
dp = [0] * n
# 初始化数组第一个元素,值为l[0]
dp[0] = l[0]
for i in range(1, n):
# 从第二个元素开始判断,如果该元素的前一个元素和大于零,则相加
if dp[i - 1] > 0:
dp[i] = dp[i - 1] + l[i]
# 否则,将初始和跟更新为当前元素本身
else:
dp[i] = l[i]
print(max(dp))