import sys

n = int(input())
lis = list(map(int,input().split()))

# max_value = sum_value = lis[0]
# for x in lis[1:]:
#     sum_value = max(x,sum_value+x)
#     if sum_value>max_value:
#         max_value = sum_value
# print(max_value)

dp = [0] * n
dp[0] = lis[0]
for i in range(1,n):
    dp[i] = max(dp[i-1]+lis[i], lis[i])
print(max(dp))